If every single event was a similar alert, there would be alert fatigue and it would reduce the efficacy of the alerts.
BC also annoyingly only has one level of alert so you can’t currently suggest multiple level handling. Most devices only handle two alert levels anyway.
There are also multiple levels of information. Many of the tweets posted aren’t things that need immediate action. It’s just a notice for people to be aware of.
And then that begs the question of why Twitter? Well because that’s what people are (or were before Musk) paying attention to. You post messages where the people are
Believe it or not there are loads of folks who think this is government overreach. But they are absolutely fine with corporations harvesting their every move.