I am struck by that bouncer being a pretty brave guy for the pay he probably makes. Being the big guy that can carry out unruly patrons is one thing.... Tackling a gunman is probably not something he expected he'd do today.
It is unfortunate that the bouncer was not able to disarm the gunman. However, his actions probably saved others from serious injury, or death, had the gunman been allowed to expend all his ammo without interruption. It will be a shame if the bouncer is among the dead, but I expect that to be the case.
I've been at clubs where even the doorman has been knifed at the venue. Leather jackets offer "some" protection. Fat and muscle too.
Doorman is not as easy as just asking for IDs.