He was also clearly disobeying repeated commands to lay down on the ground
Precisely the behavior anyone with half a brain might expect from some in public with their pants down around their ankles. Do NOT get close, do not draw your weapon, do not scream commands, do not employ tactics designed to result in death of the one exhibiting crazy behavior. IOW it is not time to play cop. You need to dump all of your cop training when dealing with the general public. It is only required to be in evidence when dealing with crooks, criminals, and politicians, but I repeat myself.
Watch the video. The big, tall and aggressive pantless man was walking fast and purposefully towards the cop and shoved or hit a person on his way.