It depends on the configuration of the attack locale. In close quarters, rampage shooters have been tackled. In incidents with space, tacklers have been shot dead.
There are no generalizations that are useful as the way to respond.
You need to have knowledge and skills to able to evaluate the particulars.
Run has worked for some. Hiding has worked for some. Playing dead has worked for some. Fighting has worked for some.
Barricades have and have not not worked for some.
The optimal response is to allow folks to carry firearms. That said - it is your moral responsibility to have the training to be able to use it efficaciously in a stressful critical incident. We need to avoid the bluster of some after a critical incident. We certainly don't need a friendly fire horror during a rampage.
We have successful firearms interventions and we have some where the intervener may have saved lives but because of failed will or tactics came to ill.
There are no certain outcomes.
Last, do not be fooled by the small number fallacy. Well known in decision making. We do not have large enough samples to make a reasonable probability statement. Because at place X, something happened is too close to chance variation.
My problem with such videos is that the fight scenario is used to argue against gun carry as you can take down the guy with a charge of the staplers and laptop of death projectiles. Perhaps, but you are not getting through Mumbai or Aurora with your stapler or gung fu. Not all rampages are close quarter let's tackle him scenarios. A well thought out Aurora attack will negative that.