I doubt SpaceX could put a satellite in orbit with KSP physics. Just the absence of realistic thermal conduction would prevent it. The outer skin temperature typically peaks around 300–600 °C during the densest part of the atmosphere. If you calculate those forces wrong the rocket has a bad day. Best case it is over engineered and has a reduced payload. They might as well do their calculations with pi equal to 3.
What does thermal conduction affect? Is it mostly practical spacecraft construction, or actually related to orbital mechanics?
The FAR mod is touted as being realistic; I haven't played it though.
https://xkcd.com/2205/ comes to mind with your pi approximation.
Nobody is saying KSP physics is perfect.
Until I played KSP, I had no idea how hard orbit was compared with just going up into space (and generally the greater population thinks the same -- they think that sending New Shephard upto 100km is about the same as sending a Dragon into orbit). I had no idea how you move in orbit, how getting from low earth equitorial orbit to Jupiter takes less energy than getting from the same ship to a polar orbit (and even then that the only real way to change your orbit like that is to go out beyond the moon and back), etc.