Your argument is that an app which is indirectly owned and influenced by the Chinese Communist Party is a conduit for free speech and the US government banning it would be infringing in your free speech... is a strange hill to die on.
There's no "unless they're Chinese" clause in the first amendment.
That aside, we're not forcing Tiktok to shut down, just forcing them to find a new owner. We're not stopping anyone from posting online, nor are we stopping anyone from posting on tiktok. If anything, this will be good for speech on tiktok, surfacing topics that were banned or deboosted by a company that has to follow the CCP rules.
In the 2000s it was the arabs, in the 90s it was the Japanese, in the 80s it was the Russians. What would it look like if we had accumulated laws inhibiting speech from each group? We'd practically have a great firewall by now.