Not legal advice. One of the fair use tests is if this work's existence would redirect people away from patronizing the source material. In Wikipedia, it's called the "effect upon work's value". One can reasonably argue that a watcher of a non-parodic unofficial recap would forego watching the full work.

I've seen recaps that are barely shorter than the episode, going over scene by scene, reading a likely AI generated script.

Actual recaps are fine, but there's a ton of bad actors there.