I mean... no?
I think it's useful to have a separate concept for actual censorship (government-mandated), and just "someone built a really great way to connect to a bunch of users, that didn't exist 20 years ago, but now isn't letting you use it". I'm not saying it's not problematic (or that it is), just that it's different in a meaningful way and therefore bad to conflate.
As for how much of a monopoly YouTube really is - it's clearly a huge aggregator that's gotten almost all "user watching video" engagement. Except other niches have been discussed here (e.g. porn), and they seem to be doing fine. So I don't think it's inevitable that YouTube is the only service that can exist.