The game has a terrible performance, you will notice lag spikes or stutter whenever a player clicks up to the next age, it gets worse if 2 or 3 players went up at the same time, this can be more noticeable watching a recording.
It doesn’t matter if you computer can handle 300 fps, late game 4x4 the performance sinks to 50 fps average on a good system, for obvious reason when a lag spike happens the latency goes really high, there is no need to upload hardware performance metrics if the game was fine before, as you said this bug was introduced during the preparations for the lords of the wets but until now it hasn’t been fixed, despite being reported a lot.
The thing is, I don’t feel the age up bug and i can play post imp 4v4 fine.
Then I still have 150fps or more and everything works really well. (Of course only, if the other player don’t have the yellow clock)
But I have to change my display mode like every 2 minutes, in order to get rid of this frame time bug.
edit: I saw the age up stutter when other people were streaming, so I know what it looks like, but I don’t have it.