Spiderverse at least had a comic book filter applied, and made it look like that low frame rate style made sense. Now it's just being used where it doesn't really belong. I can appreciate some people seem to enjoy it, but as someone who played video games where I would get a frame every two seconds (ok that was just one room in Duke Nukem 3D) I learned to hate jittery visuals and love smoothness.

I haven’t seen any of these movies but from a purely technical standpoint it would be cheaper to render a CG movie at a lower frame rate.

Movies like this aren’t rendered in real time like a video game. We’re certainly getting a lot closer to that as video game fidelity has started to catch up to CG movies. But, just as a for instance, at the time that Big Hero 6 came out the computer Disney built to render it was the second most powerful computer on the planet and it still took weeks to render.

Time is money. And if they can skip rending 2/3rds of the movie that's a lot of render farm time saved. Plus it also probably covers up a lot of animation issues.