With my arch experience, there has been a few big deal manual interventions but nothing that has bricked my install. At the worst, you boot to a terminal so you can fix it.
It usually goes like this for me:
update, oh bother... probably time to reboot
BAM
OMG WTF
open www.archlinux.org on my phone
oh geez, ok....
tinker tinker reboot
its back to normal! w0ot
I will say that I have had to learn that I need to pay attention when a new kernel is released, because I somehow get it before the video driver is also updated, it will be broken after reboot