Probably because what makes TikTok attractive isn't it's dark features that only Instagram would think was important, but how amazing it is at learning your interests with the lowest amount of required input (just swiping down quickly or not after a new video starts).

I was one of those people that thought TikTok was a modern garbage machine that only produced low quality dancing videos of young girls for zoomers. But then I read on HN that you just need to commit for a little while and it will learn what you like.

I was amazed at how much this is true. I'm now getting Scott Manley-esque space news, tech stuff, hyper local restaurant recommendations, real gameplay of game genres I actually like, etc. Basically what took me years to carefully subscribe to on Youtube was done in a few months on TikTok and it only seems to get more relevant (note: YT always still wins in pure intellectual signal vs noise).

The whole addictive thing is obviously an issue, especially for kids, but I'm an adult who grew up with tech and I've learned how to carefully balance internet/life, so it's mostly pure upside for me.