The matter is far more complicated than you are trying to portray it. The White House YouTube account was a public forum as it is understood under U.S. law prior to the comment box being locked out. The ruling in Davison v. Randall explores and specifies what that kind of forum constitutes - an "interactive space - for ANY user to post on ANY issues". This ability has been restricted after the fact on a pre-existing account that belongs to the U.S.Government, not the Biden administration specifically. It functioned before Biden's inauguration and will continue to function after Biden leaves office. The same ruling also suggests that the matter of official government bodies running online accounts should be addressed by the Supreme Court to better specify how they should be ran in order to avoid future legal conundrums. The issue is anything but crystal clear, and I'm personally of the opinion that all government accounts on social media platforms should have their comment sections open without any exceptions and should not have the ability to selectively or unilaterally remove or restrict comments. Since those accounts are ran on private media platforms, this imposition on the account holders should not (and at present does not) limit the platform owners from removing commentary that violates community standards, which technically allows account holders to report content for third-party review. That's a sensible and transparent way to run things, anything short of that is thinly-veiled shielding from criticism on an otherwise open platform. The government should not have the power to remove your ability to directly critique it - by opening a public social media account the respective public official has accepted both the benefits and the drawbacks of running one, if they can't take the heat, they should close it entirely. You don't get the honey if you're not keen on getting stung by bees from time to time. I have zero doubt that if the Trump administration did the same thing, there would be no end to criticism over it.