The Game isnt finished!
Its in Early Access, so there is few to no optimization.
You now that when you buy a Game in EA!
And i have build a massiv Factory with over 400 Machines and yes it has some lags and freezes and the FPS ix down to 30-40 but it is stil playable.
For me that isnt a Problem since I expected that, since (again) the Game is in Early Access an this for a leats one year