You’re barking up the wrong tree with your comparison of apples and oranges.
This isn’t about what private platforms are permitted to do internally, it’s about the federal government coordinating with a private platform to solicit that platform silencing people to protect partisan persons and interests, and specifically to influence public perception that ultimately affected a presidential election. This coordination with the federal government is clearly beyond the scope of what private platforms are allowed to do as a matter of private governance. This federal government interference stands firmly within the realm of the First Amendment as nakedly unconstitutional.
The Biden campaign wasn’t a governmental agency. They were a campaign. As was pointed out in the dump, both the Trump campaign and administration had done the same type of things the Biden campaign did and probably continues to do. For some reason there seems to be no concern over the Trump attempts to promote or squelch info.