The xxyyzz is a private company idea is a loving joke. Companies that large that have a platform built around speech don't get to choose what they want to see.
Except they do and can, and have full legal right.
Here's the issue. Companies like Twitter, YouTube, Facebook, Instagram, Twitch etc. want to act like they're a private company, who is allowed to ban anyone, on any grounds, promoting the content THEY want to promote. That would be all good and well... if they weren't covered by Section 230 of the Communications Decency Act. An act which protects big tech companies from lawsuits.
You can't be both a private company, who is allowed to limit the speech that they deem offensive, but then hide behind the Government when someone takes offence to it. If companies like Google/YouTube, Twitch, Facebook/Instagram, Snapchat, Reddit, Twitter etc. want to be treated like a private company, then they should allow the Government to take their protections away.