I think it depends on volume.

Once or twice a year for arguably not too major things is better than never, because it helps test the system and people won’t get overwhelmed by 1 or 2 alerts a year. Like a fire drill, but maybe slightly more useful since it actually is providing some actual info hopefully.

If they concider firing off more than that, they need to start raising the bar so that they don’t (excepting the emergency action requirement you laid out, obviously if bombs are dropping then regular alerts are justified)