I'm sure somebody else has mentioned this, but if you're willing to buy physical media, it's not difficult to rip even 4K HDR blu-rays yourself and stream from a self hosted platform like Jellyfin.

I'm able to find most of what I want to watch on physical media in either HD or 4K, with the exception of more obscure anime. Some TV shows can be expensive to pick up and more laborious to rip, though.

Older TV shows are often also only available on DVD which is much lower quality than what streaming services (and thus pirates) have for them.