The Arch wiki explicitly links to the AUR for lots of things, but the prime example is probably the NVIDIA page - https://wiki.archlinux.org/title/NVIDIA - this page is going to be massively viewed, and if you have Pascal or older architecture the suggested driver is from, you guessed it, the AUR.
Nowhere on this page does it suggest that the AUR is at all untrustworthy.
Nowhere on this page does it suggest that the AUR is at all untrustworthy.