That’s like saying “you can write whatever book you want, but the government can stop it from being sold; we aren’t obligated to sell it in bookstores”. This is a terrible argument; it conflates the government’s actions with the “bookstore”. Yes, if the app store decided to ban the app, we wouldn’t have much recourse. But the government is stepping in and saying no bookstore is allowed to sell it. That is textbook censorship (no pun intended).

No, freedom of [edit: accidentally wrote "from" earlier] speech also means that the government can't stop you from saying it. If US citizens wants to publish pro-Chinese, anti-US propaganda in the USA, and want to constitute a company for publishing a newspaper or a social media site to do, that is protected free speech and the government should have nothing to say about it.