Revolut1xn_TTV I think @Igor is right. A lot of the problem would be on the server side. I didn’t even realise this, but most (all?) of the physics calculations are handled on the servers and not locally on your PC. Once you scale this up with 8 players across thousands of matches, it must become incredibly intensive (and expensive) processing-wise.
I’ve been wondering about the performance issues on Xbox and think we should consider those separately. I run the game on an Xbox Series X, which, while not at the level of your PCs, is still pretty powerful. I actually upgraded my Xbox just to play Party Animals at 60fps, as it only ran at 30fps on my Xbox One X (which itself is still moderately powerful - although not in the same league).
I guess one way they might be able to improve things a little for PC players would be to remove crossplay, allowing them to remove any limitations imposed by the Xbox, but that would be a shame as I’ve met a few PC players that I enjoy playing with.
Sometimes I wonder if the Xbox problems are caused by Recreate having to use Microsoft’s servers. You need to have an Xbox Live account, so I suspect at least some of the traffic will go through Microsoft’s servers in addition to that that goes through the normal Recreate servers. I’m just speculating here though.
Either way, if we had more players we’d need bigger maps. Gator Velley is already a nightmare with just 8!