Have you thought about flashing a custom rom on your phone, or getting a phone that supports custom roms if you don't have one already?

I have an old samsung galaxy s5 still running LineageOS and while a little slow it's still usable as a backup in case my current phone shits the bed.

The process is fairly straightforward, and if you've installed linux on a laptop you can install LOS on a phone.

This is why I exclusively stick to Pixels. Honestly don't really care about the hardware, it's okay. But it's the only phone that lets you flash it and reflash it with a custom key so you can have verified boot on a custom OS.

Android is a tricky situation, there's very few phones that actually allow you to unlock the bootloader, and only Pixels can do it securely. Samsungs are basically a no go unless it's an older phone that has gotten cracked open. Like Samsung S5 old.

So ironically Google phones are by far the best to degoogle your phone lol, and they actually go above and beyond to let you do so. Even the new Pixel fold and tablets support this. I personally recommend GrapeheneOS or CalyxOS for these devices, both are really good.

I choose my custom OS first and then pick the actual physical phone second. For me, I value software over hardware, but obviously that's important too.

There's lots of focus on performance from vendors like Apple, Samsung and others operating in the same space. Cat phones, however, are known for having crappy perfomance due to the cheap CPUs they use.