I was playing with my hardware to identify bottlenecks (it is one big bottleneck🥲) and I found a 90 degree C GPU scenario (low resolution in the aero menu). My custom graphics card cooler fan curve didn't kick in.
I found that a hidden menu in my graphics card software had selected silent mode and was visible in ‘simple settings’ under ‘overclock’ selection which I missed as I used the ‘expert’/big head menu!
With the custom cooling curves actually working I got 52% fan speed matched with 52C gpu flat-out temperature and my old incompetently overclocked gtx950 with demanding FS2 settings went from about 45 fps to about 190 fps.
This was a pleasant surprise especially with the acute hardware shortage in the shops. I have read that gpu throttling is a combination of load, memory and temperature (or something similar), if they are all good there is no throttling. Perhaps turning up cooling can give a performance increase? I read somewhere that some throttling begins at just 30C.