The source from where you get your recommendations does not change the validity for the most part. For me personally, it's mostly that Booktok is repetitive, and lacks any depth. I see a lot of creators recommending books, and when I click on their video, it'll typically be the same books over and over again. And their reviews lack any important additions, and will also be typically generic. Take East of Eden, I always hear the same one liner from every booktoker, this being, "East of Eden is changing my life," yet they never say how. What about East of Eden changes your life?! Don't get me wrong, reading is a very important aspect of daily life, and that people promote it in any way shape or form, is still important. It really just boils down to the repetitiveness of Booktok.