Get these bands to warn the people over their PA’s they’re being shot at before running off stage!
That's just Monday morning quarterbacking. What would they say? What exactly did they know at the time?
Yeah, at first I had that thought "there should have been an announcement of some kind" but then you have to consider that nobody knew what was going on at first. Some folks heard what they thought was gunshots, so, okay, get off the stage...you're a sitting duck up there, maybe they thought Jason was the target. Who knows.
Instead we should consider "how would I react in that situation?"
Would I recognize the sound as gunfire, and more importantly, that it was coming *at* me? And then what? Do I duck in place, or do I find cover? Where is the nearest cover? Am I responsible for those around me, or are my friends/family my #1 priority? Am I more at risk from the gunfire, or from a panicked crowd? So, do I shelter in place (behind a sturdy barricade) or do I join the throngs for an exit and hope I'm not trampled?
Now think about what impact a PA announcement "get out of here! That's gunfire! Run!" would have on the crowd. The casualties may well have been much higher, and that's just from the stampeding herd effect.
Or maybe not, it's impossible to know, which is why it's pointless to attack the concert organizers for not making an announcement.
I say all this with all due respect, I don't mean to criticize you or anyone else who may share that view. I merely want people to think it through is all.