I haven't had it often but I've had stuff break sufficiently badly that I couldn't boot to a graphical environment before.

I agree with the other posters that a lot of the stuff that breaks is in the AUR, but practically most users rely on the AUR so if the AUR is prone to breakage so is the typical user's arch Linux environment.

I'll also freely concede that part of this stems from the common practice of treating the AUR and pacman packages interchangeably through helpers, but that's a practice that's almost necessary for reasonable use and is present on the official wiki.

I think ultimately Arch is just a UX which was designed in a simpler time when users could reasonably expect to account for all the packages they installed