Why do you call it junk? Is everything on YouTube junk, because there are some really bad and fake prank jokes? Is everything on here junk, because some people don't have the best intentions?

Seriously, even in Germany the public opinion about tiktok is so much influenced by people not even having used the app even once (seen some of the good parts of it).

Meh. If it were worth archiving then someone would be trying to archive it. Nothing the US law is doing would prevent that, even from within the US. If you're really concerned, then start working with ByteDance or archive.org or whoever to actually preserve the data instead of whining that somehow it will be "lost" because you can't install the proprietary reader app from within the USA.