What we do know is that one unarmed mother did...
My bet is, even if you are right about some of the folks on the board that many of them would have gone in there. Of course you assume that they are all just "keyboard warriors" not volunteer firefighters who regularly enter dangerous situations to protect others (I know that at least two of us are exactly that). This is something I doubt, it is likely that some of these folks volunteer to protect their community in some manner. It is also my guess is that if your kid was in there and the police waited over an hour to go into the school you would have been chomping at the bit to go in your damned self because they were not doing what you know was the right thing to do. You know that this police force was wrong to wait, we also know that their excuse that they "just couldn't get in there" was BS as that mother did.
After Columbine police forces changed their policy on mass shooters and stopped assuming that it was a hostage situation, this "police force" was just a "bit" behind the times (by a couple good decades).