Why should YouTube have a megaphone to give in the first place? Last I checked, there are still laws on the books to handle companies with >90% market shares. [0]
Good, so we agree that this is not an anti-censorship issue but an anti-trust issue.
Private entities can't censor anything, anyhow. Independently and freely choosing which sentiments to platform on a private service is not censorship, no matter how far anyone tries to stretch the definition of the term.
I just checked a couple of definitions in case my memory was failing me, but I don't see any definition of censorship that limits it to governmental action. YouTube can and does censor content on their platform, I don't understand why so many people seem have trouble with that word. All it means is (quoting Webster) "to examine in order to suppress ... or delete anything considered objectionable"
The way it's being used in public discourse is not necessarily the dictionary definition of the term. You have to meet people where they are when it comes to rhetoric, not try to force them to follow your version of what means what.
YouTube chooses not to display media uploaded to their servers. That is not censorship, that is discretion.
Censorship is going around to all the platforms and forcing them to remove content which has already been or is on the way to being displayed to the public.
The way "censorship" is being used in public discourse, in practice, seems to be that it's not censorship when it's applied to views the people driving the public discourse disagree with. Remember the controversy over LGBT content supposedly being removed or demonitised on YouTube - pretty mucn none of the mainstream discourse agreed with the idea that it wasn't censorship because YouTube was a private company, let alone the idea that - as I've seen pushed in other areas - that pressuring YouTube not to do it was actually the real attack on their free speech rights.
1. the suppression or prohibition of any parts of books, films, news, etc. that are considered obscene, politically unacceptable, or a threat to security.
2. (in ancient Rome) the office or position of censor.
Yes, but back then we had the party organ of the American Nazi Party and the party organ of the International Workers of the World, and a couple more in between. You could buy them, and you know what you would get. Now you just have Youtube. That is a problem.
Modern capitalism has replaced the public square and a huge number of face-to-face communication opportunities with communication mediated by private corporations, and it uses those (and they take liberties themselves to for their own purposes) to outsource censorship and stiffle public discussion...
The idea of restricting freedom of speech to the state is an antiquated idea, belonging to pre-internet times, when a huge part of social interaction didn't happen through social media...
[0]: https://www.statista.com/topics/2019/youtube/