Good thing that the nut chose the hundred 100 rd 'beta mag' that is prone to jam instead of regular 20 or 30 rd magazines or the carnage would have been much worse.
Thank you. I have been saying this for many years now. The North Hollywood shootout involved drum magazines as well - cheap, unreliable magazines that are prone to jam. If this shooter had been using standard 30 round magazines, the damage would’ve been much worse. 100 round magazines (and even 50 round magazines) are novelty items and nothing more. The military doesn’t use them because they are garbage.
In this case, high-capacity magazines saved lives.