People try to use Manjaro as Arch when it isn’t Arch. Manjaro has it’s own repositories that may not match Arch version. You install an AUR package that depends on an up to date Arch package to work and it fails.

Because manjaro does weird stuff with own repos etc

It’s literally the worst distro, https://github.com/arindas/manjarno

Endeavoros is fundamentally better in every way, everything manjaro adds makes arch worse, and everything good they have comes from arch.