In the wider realm it's a mixed bag, but advertising really does not seem necessary.
Wikipedia is an outlier that goes through intense fundraising to survive. It also does not produce content.
NPR has lots of advertising: https://www.nationalpublicmedia.com/npr/platforms/npr-org/
Media publications are businesses and they need to make money to survive. Donations never work and if you tried to pitch that as the business model at even the hippiest startup convention, you'd be laughed off. Subscriptions do work but the public does not understand how to price the value and would rather go to starbucks instead, clearly seen in the endless comments and downvotes on HN when there is paywalled story or advertising talk. Subscription also bring up the issue of access for people without the means to buy.
20% of NPR's funding comes from corporations. Useful yes, required no.
It feels like advertising, but in practice it's virtue signaling. Much like giving to Habitat for humanity corporations want recognition for their donations, but as pure advertising it's not worth it. So, if they where not mentioned on air corporations would likely cut back, but not to zero.
Virtue signaling is still advertising, paying money for exposure. Otherwise it's a corporate donation and that does not scale at all. You can look at the continuous travails of open-source projects that deliver billions in value but get no funding as a perfect example.
The point is that NPR comes nowhere near the massive amount of content that people consume but don't pay for. Please don't just assume the entire industry is incompetent, there are millions of people working in these media companies and they are constantly trying new options. So far, outside of subscriptions for certain high-end brands like the Financial Times, advertising is the only sustainable model found.
Click bait is an outgrowth of payment in eyeballs.
As to virtue signaling, I bring that up because it can occur even if they are never mentioned on air. A company can say they are a corporate sponsor of X even if X only ever mentioned them on an obscure part of their website. In the world of virtue signaling simply accepting money creates vale. NPR is behaving rationally to accept as much money as possible and even to put effort into getting more because at effectively 90% the funding they would create less value, but clearly they could still create significant value with 90% of their current funds.
Anyways, if advertising went away, a massive amount of media you see today would also disappear. You would definitely notice that.
And that's before even getting to the even more massive impact it would make on the economy since every major company today relies on advertising for growth and sales. It's easy to look at few annoying banner ads and say that they suck, but this is a 12-figure global industry that plays a critical part in the economy. It's just not that simple.
Advertising is largely zero sum, it increases the cost of products while increasing individual product sales. People would buy almost exactly the same amount of food for example without any advertising so that's pure dead weight to society. Despite all those car ads people would still buy a car without them further without that massive cost those cars would be either cheaper or better, etc across a huge range of industries. Without ads people would still buy soap and other home goods, at worst they would pay less when doing so.
I personally have no interest in seeing any kind of ads and indiscriminately block all of them. I'm perfectly fine if that causes companies with ad-based revenue to go bankrupt, and there is not slightest legal or moral obligation for me to support these companies.
If you have a company and worry about ad-blockers, the first thing you need to do is to create a product that you can actually sell.
Of course, as long as they don't complain and stop whinning about ad-blockers, I have no problem with companies who base their revenue primarily on ads. I'm simply not one of their customers.
It's not about ad-based revenue. Every single company relies on marketing for success, and so the economy is tied to advertising. There's a reason that some of the largest companies in the world are advertising businesses. People are also bad at judging value and dont/wont pay for things like news. Like I said before, plenty of publications sell subscriptions but HN threads still whine incessantly about paywalls, while also ignoring how many people can't afford to pay but would still like access.
Also, adblockers are not really a big deal, there are plenty of ways around them, especially if you want the content, and you're at best blocking about 10% of the advertising that's reaching you anyway.
Advertising is the fastest, easiest, most scalable, and most egalitarian method there is.
The actual issue people seem to have with is the modern online implementation that is slow, invasive and frustrating. There are companies doing a better job and things will get cleaned up but there's nothing wrong with the concept itself.