The point was an extremely limited point that the event doesnt prove a gemara wrong.
And people dying is not an indication that the psak to stay was wrong either.
Obviously I’m not addressing anyone who clearly said “it will be safe”. That’s probably best understood by gavra’s last comment. (the premise of which, GAW – by the way – is that you should ALWAYS listen no matter what, because if its misguided then that too will have been whats supposed to happen).
But there many others. R’ Elchonan knew the situation, for example, he said himself he was going back to his death (or something to that effect), and still advised (at least certain people) to stay.