Read through the link i provided. The major point i take issue with, is their package repository. They basically delay every package for a few days to call them 'stable'. This behavior makes it by definition incompatible with the AUR. One of the major reasons so many Manjaro systems break. The other reason is their awful package manager.

I ran my manjaro install for over 3 years but never touched pamac and instead used pacman and paru. I was simply too lazy to set up another distro at the time.