That is one fucking tie if you ask me.
He has direct motive to influence the operations of the American state, the resources to amplify his messages, and has control of a platform that's mainstreamed in a way that gives it a broader reach than TikTok ever had.
Saying he's an American entity is barely meaningful. When you're that rich, you can probably pull in five new passports given 48 hours notice, so the one you carry at any given point is largely a flag of convenience.
Blaming China is a cheat code for the current political climate. See the Huawei fiasco: No level of audits, disclosures, or actual technical evidence about security would satisfy-- It Is Foreign So It Is Evil. So I'm sure that the hype against TikTok was fanned in part by their competitors who saw an opportunity.
I'm seeing a lot of attempts to render Tiktok as interchangeable to any number of other examples in order to pose a dilemma about logical equivalences. I just don't think these withstand factual scrutiny. Rumble is not at the scale or engagement of Tiktok and Twitter does not have ties to a major competitive state actor.
You can see how it's meaningfully differentiated if you want to. If you don't want to, you attempt to restate the terms on which the comparison happens to make it look for fuzzy, so everything looks the same.