The platform vs publisher argument isn't about which are vulnerable to government censorship. It's about those places (social media, search engines) purporting to be platforms engaging in censorship, but retaining the platform protections.

Platforms are protected from legal liability for what users post. Publishers are not. To be a platform you can't exercise editorial control over the posted material outside of barring actually illegal things. Every social media corp that engages in censorship of opinions they dislike should lose their platform protections. Since those corps have been censoring users, often in behalf of the deep state, they should lose liability protection.

If you took liability protection from facebook or google or what have you, they'd either instantly be destroyed or be forced to stop being censorious goblinoids to regain their protection.