In my experience, Kindle Unlimited is crap anyway and in no way or form "unlimited" like e.g. Amazon Music is. Almost everything covered is extremely low qualit

In my experience, Kindle Unlimited is crap anyway and in no way or form "unlimited" like e.g. Amazon Music is. Almost everything covered is extremely low quality. And the very few books that are worth reading and eligible are cheap anyway (because they're likely self-published), so you'd save money just buying a couple of those every month. (And you'd even get to keep them!) I'd be intrigued to hear opposing viewpoints. OTOH if you see that a book is covered by Kindle Unlimited, that's an indicator that it's probably not that great so that's kind of useful when you're looking for something to read. :)