

Not every PKGBUILD contains a .install file. So again, it is not inherently the case that you’re “literally executing random shell scripts by strangers as root.” slackness has it right that most people probably don’t read the install files, but it seems to me that their prevalence in the AUR is overstated here.
What am I making up? That most AUR packages don’t have a .install file? You couldn’t be bothered to say what I got wrong or provide any evidence to back it up so I can only assume. But if you have issue with me speculating about how common .install files are in the AUR, fine. Here are some numbers.
Out of the 2500 packages I analyzed, only 19.08% of them had an
install
list in their PKGBUILD. One could very easily use the AUR and never, and I quote, “literally [execute] random shell scripts by strangers as root.”I also dug deeper regarding your claim that install files “don’t have to be explicitly mentioned in the PKGBUILD if it shares the same name as the package.” I can’t find any evidence of that. It doesn’t have to be listed in the sources, which is probably what you meant.
Clearly these couldn’t be the things I’m wrong about, so I await your careful clarification.