This scenario is under the assumption that P1 fired the first bullet before P2 can even react. Now I know this sounds crazy but unlike console most people can aim on PC. The majority of the time this scenario plays out P1 wins by default before P2 can even react at all hence why there’s a flood of people talking about how garbage the TTD is in this game.
Then if you want to take a head to head gunfight into account it’s literally just throwing dice on a table to see who wins because the netcode in this game is so bad that even if you have lower ping and shoot first the server could have already decided that guy was firing his gun half a second before it even registers on your client. The longer the TTK the longer the server has to actually register what the ¯_(ツ)_/¯ is happening in this game.