Sure, but limiting speech in your private forum isn't squashing free speech.
Unless your definition of free speech is being able to say whatever you want whenever and wherever you want with absolutely no consequences from anyone.
Not inviting a friend for lunch because of their annoying Taylor Swift obsession is, by that definition, squashing free speech.
Unless you have effective monopoly control over what constitutes the only viable platform for a particular medium. It's entirely disingenuous to claim that YouTube is now simply a "private forum." What if Amazon declared that black people couldn't sell on their "private" infrastructure. Would that really seem fair?
Not inviting a friend for lunch because of their annoying Taylor Swift obsession is, by that definition, squashing free speech.
No, the proper analogy would be the de-platforming and demonetization of Taylor Swift and her fandom through underhanded and non-transparent means.
No. Nefarious motivations, such as a desire to exert power by controlling discourse, can be judged by actions, and they should be considered in terms of the kind of future they can bring about. It's well and good to judge someone's credibility with regards to talking about human rights, by observing what they would do with human rights.
Your argument is essentially "this is wrong, because I think it is wrong".
No. Squashing free speech in effect is dangerous, because it's through speech and discourse that a society such as the present one can avoid bloodshed. It is wrong because it is dangerous. It is wrong because it is against a human right, which under-girds all other human rights. Those who are motivated by power, for which rights can be sacrificed, have a very bad historical record.