I think those alone would be grounds to at least take a close look at his access to Twitter data, his censorship choices and any input he has into the algorithms.
We can't just ban everything though. It'd be better to just allow everything.
Honestly X is pretty crazy on the propaganda these days, it's a little scary. The issue with TikTok would be way more subtle or speculative. Anyway if it is "unacceptable", I don't want that to be for the govt to decide. Even if it was being overtly politically manipulative (which is less scary than being subtle I guess) - I'd still support it. I like consuming foreign media, recognizing bias, being exposed to different view points, and thinking critically to make my own decisions. If you don't think the average american can do that, well too bad, we can't just spoon-feed people "approved" content.
But control of an algorithm that can shift public opinion in ways that are imperceptible through promotion / demotion of posts on certain topics, is a different matter altogether. And the CCP are masters at this (since their own social networks in China are heavily controlled).
I 100% agree with open access to all sources - but you should know what the sources are. If the CCP secretly owned the NYT, that would be a problem as I would want to know that when I read the NYT it's likely reflecting CCP authorized views, just like I know what to expect when I read the Economist, WSJ, or The Times.
Basically what Twitter was before Elon bought it.
None of this is a normative statement - I’m not saying that this is good or bad, but if you want to know why the US government thinks Elon is better than ByteDance, it’s because they can shoot Elon tomorrow if they decide to, but they can’t shoot Zhang Yiming without causing an international incident.