I still think the performance is quite poor on PS5 considering what the game is, but I have figured out one of the real problems that I have, and it's the camera in build mode. 

When in the free place mode things are mostly fine outside of the performance dips that I don't think should be happening.  When in the grid based mode the camera sticks to/rapidly skips between every grid line that you pass over, making the game look like it's lagging and stuttering and probably giving people (like me) a fair amount of motion sickness.

Please find a way to smooth out the camera movement in build mode, I don't remember things being this way in TPH and TPC.  I also don't know if the camera is like this on PC or on Xbox, but it's certainly a problem on PS5.