The speed of your simulation in a game like this should have minimal impact on the framerate of the game. You can paint the screen 144 times a second, but only tick the simulation 10 times a second and get a much better experience than painting the screen and updating the simulation 20 times a second. Maybe your city runs slowly, but you can still look around at the various bits moving slowly.
Not trying to be rude, but this honestly reads like you don’t actually play simulation/4X games.
> Maybe your city runs slowly
If the simulation is running slow that has a much more detrimental on the quality of game play than jumping from 45 fps to 75 fps. Sure, it’s a simulation, but it’s primarily a game, not a weather model. And I say this as an early adopter of high hertz monitors and a frequent fps player. I absolutely need high frames and low input latency in a competitive PvP game, but in a strategy game, it’s much more important that the tick rate is fast enough that it’s interesting. A slow sim is boring, and it’s not just me, people complain about this all the time in (late game) Stellaris(another Paradox title).