Using the AUR in general can lead to breakages as packages in the AUR are built on your system upon install, so you are responsible for understanding when you need to rebuild those packages to keep things functioning.
This can be made worse on Manjaro because they hold back updates from its base distro Arch, which can lead to breakages if something in the AUR was updated to require something new in the Arch repository, be that a new dependency, updated version of an existing dependency etc.
It can also cause issues because to my understanding Manjaro just holds back on all updates hoping Arch users find all the bugs. So if something was broken, but a fix was pushed in Arch it can take longer to reach Manjaro users.
If you want Arch but hate manual installation or the arch-installer, just use EndeavourOS its changes are more focused on making the install less tedious and theming. In my opinion you will get less issues on Arch and EndeavourOS than you get on Manjaro, which seems be a fairly common opinion.
