I don't think discovery is what TikTok offers either but admittedly I have only seen it in action third hand. How often do you see things that are truly novel to your interests?
My impression was that it's no different to other feed based apps in that it hones in on a few topics and you end up in a pretty narrow content bubble.
That is where it really stands apart- while it can get hyper-specific, its consistently mixing novel content types. Some has appeal based on a look-alike type of matching, others to general appeal, and more still to new and small creators. Once it has a sense that you're in a session you're not likely to abandon it takes greater risks on trying fringe content. Let me put it this way: give it a solid 2 weeks and you'll start discovering new parts of yourself.
My impression was that it's no different to other feed based apps in that it hones in on a few topics and you end up in a pretty narrow content bubble.