"BookTok" is not responsible for what sells
I am consistently running into the idea that "BookTok" is why xyz is popular. It's most often aimed at something the speaker doesn't like, be it a trope or spice level or genre.
But here's the thing: if people don't like a thing, all the free advertising in the world isn't going to make it popular. BookTok is not a magic wand. It does not grant wishes.
The only thing BookTok can be accused of is potentially exposing people to things they already want to read, or would want to read if they knew it existed. And if a trope or genre falls out of popularity, it won't because BookTok drove it to suicide. It'll be because that trope or genre stopped selling, making some authors abandon it.
The things that you prefer just not being popular compared to the things you hate is just the case of you being out of step with a majority of readers. And sure, that can be a little frustrating, digging through a comparably handful of authors for what you want versus the deluge that whatever is popular has (ask me how this feels as a sci-fi romance lover). But deciding that the popularity of X thing is not actually popular because of "BookTok" is just eye-rollingly ridiculous. It screams, "Well, the football quarterback wouldn't like her so much if she weren't pretty and a cheerleader!"