I haven't looked that often since it is easiest to try to avoid software that isn't in the main package system, but I rarely see PKGBUILD checked into the upstr

I haven't looked that often since it is easiest to try to avoid software that isn't in the main package system, but I rarely see PKGBUILD checked into the upstream project. It is more common in my experience that an upstream developer manages the AUR package on the Arch website, not as part of the project. You can verify AUR packages before using them (this is what I do) but it is an extra step vs. a maintained PPA. AUR packages can be unmaintained as well. No matter the system the best situation for users is when the software you use is in the main package system.