1A protects us against censorship, and this law is precisely that. If I have TikTok and I use it to communicate, the government is censoring my speech by taking it down. There is a lot of case law on when the government can legally censor speech, and I’m not going to repeat it here, but the government’s lawyers have a massive hill to climb on this one. Maybe they can succeed, maybe not.
There’s other precedent about “making a specific business illegal”. Essentially, legislatures can make conduct illegal, but courts don’t like it when they make businesses illegal, because it’s a violation of due process. But this is complicated and detail-specific.
Anyway, there’s a lot of great information online about these two legal arguments. I encourage you to look it up.