what's stops one from scavenging the best parts of old phones and putting them into a new one?
These are just examples, I have no opinion on what is the best.
Something like: I like the cameras from the Galaxy s23, the processor from the latest Pixel, the memory from the Razor. I mean whatever. I suppose Iphones could be included, but I figure it's more locked in than androids, I could be wrong.
Or even replacing a part from one phone with one that's better, for personal use? Like, even just putting pixel 7 cameras into a pixel 8 phone.
Besides the factory warrenty, and money spent, is it software? Is it having to reconfigure the hardware? Is it just space in general?
If we all have things we don't like about our phones, why aren't we able to just make it more to our liking?
All of this stuff is usually fit onto a single board, crammed into a very specific amount of space, and is thoroughly and iterated until it works properly. This isn't the kind of stuff a home lab does, but you could certainly try. I think it would be damn near impossible to do it better and more reliably than teams of hundreds or thousands of various engineers. It's not like you can just take a phone CPU and slap it on a random board without a ton of forethought.