I'm not sure that "critical infrastructure" as regards to communications mediums and legislation should be understood in the terms of absolute necessity, rather by terms of popularity and wide usage. That wide usage brings with it a lot of power on the part of the platform owners and a certain immunity to being boycotted or replaced.

The critical question is if they ought to be allowed to wield that power unchecked, up to and including when that reach has progressed far enough to have real impacts on our political system, and so impacts on people's lives.

Remember, we're talking about what we'd like the law to be, not what the law is. These definitions are up for debate and redefinition.

Of course they ought to be allowed to affect the political system. The whole point of the First Amendment is to ensure that private citizens can act to change the government—the fundamental concept behind the design of the U.S. federal government.

News organizations have wielded this power for at least a century. Their decisions on what stories to publish obviously have political implications, and in some cases their editorial boards even explicitly endorse one candidate.

Facebook and Twitter are private entities, just like The NY Times or Fox News.

So you see no problem whatsoever with large, nigh-monopolistic interests having absolute authority over how politics is discussed?

This is not a strawman, I simply see no other way to interpret this comment.

Social media are specifically not publishers, so no they're not "just like" the NYT/Fox.

They don't create content as an organization and only facilitate communication, which is exactly why section 230 is being contested.

Section 230 applies equally to any interactive computer service, whether it is operated by Twitter, Facebook, NY Times, Fox, Ycombinator, or even you or me.

The First Amendment applies to everyone in the U.S.

Yes, and since social networks are only third-party content, they should not be interfering with it otherwise they are exercising editorial control and are now first-party content.

I said communications medium, not infrastructure. Life goes on fine when the internet is down or your phone is disabled, but they're still considered important and necessary.

Facebook and Twitter are just 2 of the biggest with many others like TikTok, Whatsapp, WeChat. It's the size and scope that should be used as a measure of when they cross over into public utility vs private project.