While they have no evidence of big problems this sort of thing causes issues. Idiots use the alert system for stupid things, people respond by blocking them.

I've seen it locally, dodgy cell phone area, we were all being bombarded repeatedly about a missing hiker. The network apparently didn't understand and sent it every time we entered service again. There was some discussion of how to turn it off--that despite the fact that we were all hikers. (And, fools, a couple of us could perfectly well piece together what had happened. Her body's out in the desert, she didn't go to the mountain *that day*.)