PvP combat in Project Zomboid is broken, and even now even if you play two players. You will have serious desychronization (aka void on the road). And it was obvious from the beginning because the game was positioned as a single player. And most likely the game engine was not originall...
I remember when they originally added them in to make it infinitely harder to get in to and nerfed the total gun loot outside, it was a genuinely good balance change because running there first thing, cracking the window open and closing the shutter then bolting for the armory was...