They can be really stable. I think your milage severely varies on how much you know what you’re doing and how careful you are in respect to certain things.
Personally I’ve been using Arch for 5 years and I haven’t really had any problems with things breaking on updates.
Here in Germany the current big “conservative” (which is increasingly radicalizing itself to the right) party, the CxU, is taking notes big time from US political rhetoric and they’re far from the only ones doing it.