I'm not sure that's true. Neither I nor most people I know who use Arch (granted, most of them are professional software developers) install software from the internet willy-nilly and without reviewing anything, if by AUR or "curl | bash", especially when on their main computers.
Citation needed.
Archlinux is a distro that’s designed for the user to control their own system, and the AUR is clear about what it is and the nature of the packages in it.
> Warning: AUR packages are user-produced content. These PKGBUILDs are completely unofficial and have not been thoroughly vetted. Any use of the provided files is at your own risk.
This is from https://wiki.archlinux.org/title/Arch_User_Repository.
> Warning: AUR helpers are not supported by Arch Linux. You should become familiar with the manual build process in order to be prepared to troubleshoot problems.
This is from https://wiki.archlinux.org/title/AUR_helpers.
"yay" is one of the most common AUR helpers, it requires two confirmations from what I counted. One of them is to inspect the PKGBUILD file, the other one is just to proceed.