Oi - where to start - let's go one by one.
>> Because US/western social media has same market access to PRC
I do not believe that the preferred platforms of the CCP, owned and operated by the same people, would not be favored in China. There is no open or transparent lobbying in China. Rather, overnight, someone from the CCP can decide that your platform should be shut down and your employees harassed, arrested and/or prosecuted. Yes, the market is huge, but why would any western company take that chance. For all its flaws, the US doesn't have these issues to this level. The TikTok debate is happening relatively slowly and a lot of it in the open (So our politicians can showboat, but still). TikTok also has access to the best lawyers, lobbyists, as well as grounds for appeal. Those in power will also be politically assailed by their opponents on behalf of those under 35 for shutting down their favored platform. People could conceivably lose office for the decision.
>> Forward to today, somehow TikTok operating in US while compliant to US laws managed outcompeted US platforms.
No argument here - TikTok has done amazing and has played by the rules (though if you have pile of nearly infinite money from a powerful government, you can do a lot). I'd argue that realpolitik, is alive and well, always has been and always will be. TikTok can both influence (which I'm less worried about thanks to the other avenues of free speech) but TikTok can also collect and retain the moral and legal trespass of the young for decades to then use it as blackmail when they are the ones seeking positions of power. You could argue the same for all the other socials, and I think their data retention is what should really be limited, but they are at least within the confines of a legal system, that yes, has flaws, but is open enough.
I'm not naive enough to believe the US is devoid of corruption, backroom deals, people whose rights are denied or trampled on etc. But compared to the CCP's framework, there is no debate.
Personally, I think TikTok has a first amendment right to exist regardless of who owns it. It's the data retention that really worries me, and unless you count data as property (which I could be convinced of), there is not right to data retention.