not entirely unexpected given
I will not judge your decision regarding update - it is how you choose to do.
While Manjaro certainly is easy to install and - suffice you don’t use AUR and do not use some obscure unsupported theme - it is not problematic at all - not even Plasma.
I don’t have a straight answer - no one does.
The Manjaro Linux system allows the user to do whatever they see fit - and only minimal safeguards exist - e.g. the package manager will not immediately let you remove a package required by another package - but if you insist - the package manager will bend to your bidding.
So I suggest you do some house keeping - this may solve some of your issues - no promises though
If your system is using an old Nvidia card - issues are to be expected.
I have an anecdote I sometimes refer to
I have this friend, Bernt, which is a retired high mathematics teacher, with a curios scientific mind - but not with computers, ask him about the golden ratio and fibonaci numbers then he’ll keep you busy for days.
He bought this bamboo pc from a collegue at work - with some kind of grey licensed Windows on it.
At some point during update, it went bonkers - I don’t remember 5-6 years ago maybe - and he asked me to help perhaps around the time windows xp as finally discontinued.
Knowing there is no Windows I cannot offer him to reinstall - and I don’t want deep dive into an unknown Windows installation - those days are long gone.
So I offer him to install a Linux - Manjaro Xfce - I heard from him once - he couldn’t remember the password for updating - no problem - just use your user’s password.
I recently heard from him - he forgot how to update - but the system is still running and he is mighty satisfied
He doesn’t tinker - he doesn’t change things - he just keeps the system up-to-date and it just work
The morale is
- if you don’t tinker with a Manjaro Linux
- update when update is due
- it will keep working, day in and day out - for years - no issues