Without moderation things quickly become a cesspool. Whether spam, or child porn, or scams, or just extremely toxic behavior that scares off 99% of users the end result is the same.
Moderation of content - some form of censoring - is a feature, not a bug.
Nothing is stopping you from providing your own video platform that doesn't censor content (or at least doesn't censor any legal content). The free market, however, is unlikely to support you in that effort. Advertisers have always refused to sponsor content they find objectionable, and most people won't pay, so that leaves you with rather thin margins for such a service.
I agree this is true in theory, with the internet as it is today. PragerU can and should host their own videos if Google doesn't want to (edit: though in this case the problem is not related to hosting but advertising, it seems?). Anyway, we can and should criticise Google for their partisan stances and they shouldn't be treated with much sympathy if a conservative government retaliates in some way either, but that's by the by.
The problem is that this sort of thing doesn't have any limits. People were making the exact same argument when Google seized the domain of a source of unpopular speech such that the owners were not only unable to use Google's services, but in fact, were unable to host themselves too. It was basically a DoS attack by a corporation on that site.
The internet is run entirely by private companies. What happens to your argument when someone does in fact stop PragerU from providing their own video platform that doesn't censor content? For instance because an angry mob tries to shut down your ISP, or a DNS provider steals your domain, or a DDoS protection firm decides not to protect you anymore and then lets an anonymous mob take your servers offline?
Nobody at any point has violated the constitution, but the outcome is identical. Digital technology requires private sector collaboration. If an increasingly partisan set of tech firms systematically try to wipe conservative thought out - which is what they are doing - despite that this political philosophy represents about half the voting population, then they are going to end up regulated so strictly it'll make banks look like free-wheeling anarchists in comparison. This will happen slowly because conservatives don't want to do that, but it will happen, especially as actual shrink-the-state conservatives don't tend to get into leadership positions in the west.
Ultimately the right to criticise the government is a right to criticise those who have power. The arguments for it don't change if the government outsources suppression of speech to contractors, and don't change if a bunch of political allies manage to take control of organisations required to engage in speech. It's the right itself that matters.
PragerU is a corporation as well, so I'm not sure what you're getting at here. But this decision is absolutely consistent with applying the First Amendment to corporations.
Compulsory speech is not free speech. Why should YouTube be forced to spend their time and money to disseminate PragerU's content on their platform — i.e. to "speak" against their will?
PragerU attempted to argue YouTube infringed PragerU's freedom by arranging that metadata in a way PragerU didn't like.
It comes from the body of everyone who holds shares in the corporation. Banning free speech from corporations would increase the influence of billionaires, not lessen it, by making it impossible for those who don't have the means individually of purchasing distribution from banding together and purchasing distribution as a collective entity.
Concrete example: let's say there's an evil billionaire, Lex Luthor, who's flooding the airwaves with propaganda for policies that you think are awful and evil. In a world where corporate speech was prohibited or restricted, you and your neighbors would have much less power to oppose Mr. Luthor, because you would be unable to band together and form a corporate entity (e.g. "Concerned Citizens Against Kryptonite Pollution") to oppose Mr. Luthor's advertising that kryptonite is a perfectly safe chemical which has no negative health effects.
Billionaires own, or control, PragerU, both in funding and board seats.
So they get the best of both worlds - the ability to use corporations to speak on their behalf _and_ shield them from the consequences.
The real "problem" is that the US has the First Amendment, which guarantees both free association and free speech in a relatively absolutist manner. Unrestricted corporate speech is a result of the confluence of those two conditions. I can associate with whomever I please, so long as it is not for a criminal purpose, and I can say whatever I want (subject to the usual restrictions around threats and direct incitements to violence). So of course, I can gather with like-minded individuals to say things more loudly.
I don't think the solution to this "problem" has anything to do with speech laws. The root cause, as you pointed out, is the massive disparities in wealth. If we addressed that, then the problem of the wealthy being able speak more goes away, without us having to weaken the First Amendment, a step I am very averse to taking.
We, as many societies, will have to deal with the other large question: what do we do with monopolistic mega-companies?
The Youtube question has to primarily do with that they're the primary go-to for videos online that aren't related to pornography. There is Vimeo and other tiny video sites, but none of them amount to the connected monetization platforms, like the way Google does with YT.
Traditional monopolies don't really come into place, because as the canard here on HN is, "You can just make your own video site." In reality, that ignores all the interconnection and entrenchment. But Google doing X doesn't mean you can't. Are they a monopoly? (I believe they are.) And if so, what restrictions should they have in place to be fair?
(As and aside: I am arguing this in good faith. I've seen and had friends deplatformed for infosec, hacking, and gun repair videos on YT. I've also seen similar on FB and Twitter as well, with no recourse. And on FB and Twitter both, my elected politicians show up and talk with the populace. But alas, my first comment sits at -4, for what I guess is as a 'disagree button'. )
Why draw the line at pornography? It's legal and protected speech (at least "mainstream" porn, not talking about child porn or anything like that).
It's easy to say "well obviously YouTube isn't going to host that!", but it feels if we're going to compel them to platform speech they don't like, why would it stop at porn exactly?
NOTE:
I disagreed with your point above but I actually upvoted to offset some of the downvotes. HN really should reserve downvotes for problematic stuff or spam, not just people disagreeing where to draw the line for free speech.
There's nothing illegal about being a Nazi (at least in the US), but advertisers typically don't want to be on the same platform as Nazis (for good reason). Are you claiming that advertisers should be forced to advertise on platforms that they don't agree with?
NOTE:
I'm not claiming that PragerU is outright Nazi propaganda. I think they're a terrible organization and their videos are idiotic, but I haven't seen outright Nazi promotion on their stuff (though admittedly I haven't watched everything by them).
As real flesh and bones individuals, the first amendment protections should apply.
For companies (aka: fictitious entities), are granted corporate charters by the government. They are extensions of the government allowing a bubble of state/federal government of what we call a company.
Freedom of speech makes sense when its my body - but who's body does the speech come out of with a corporation?
In that light, companies should have a requirement to uphold the bill of rights. They are created legal entities, not at all like a person.
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The glaring problem with not applying 1FA to a company means the mega-companies that wish to deplatform you leads you to no recourse. Do you have a right to use a monopolistic service?
The issue with that course of actions is that the rules to the megacorps (FAANG) also apply to the small companies with 1 or more. More regulation does tend to kill tiny companies.