While I agree with the sentiment, this scenario set up has a weakness that allows criticism: it is purposefully designed to make it difficult for the participants by adding the helmet and the gloves. Without the helmet on in some of the cases, the participants would have better peripheral vision. Without the gloves on, some of the participants may have had better access to the holstered weapon. Also, the way the weapon was holstered and hidden under the shirt may or may not have been the preferred holstering location for those users, making it unfamiliar for them to access instinctively. It's not clear, but I'd assume that the instructor probably knows who has the weapon and it seems like in all cases, the person with the weapon is sitting in the same area of the class room if not the same exact seat, giving the instructor an advantage. Finally, knowing that this was a set up would have elevated their anxiety and changed their mindset from a "normal" state where they would not have been starting from a prolonged and elevated level of anticipation.
Helmet, gloves, and all factors considered, though, the participants would have likely made the same mistakes: not covering ("hero syndrome"?), tunnel vision, not considering collateral damage, etc.
To be clear, I'd believe that most people would have the same issues in real life scenarios; just pointing out the weaknesses of this experiment.
Can they replicate it with lazer tag devices? Also, I think i'd be worst in a real life situation compared to a simulaiton.