I have an AMD GPU/CPU (RX 6800/Ryzen 5900x) and a 120Hz monitor with freesync turned off and Vsync in the sim turned on at 33% which equates to 40fps locked.
The fact of the matter is if I did not have vsync turned on in the sim, my GPU and CPU would be forced to work flat out to achieve the refresh rate of my monitor (120fps). That would involve fans blaring and enough 
to heat my house and I’d only get to 120fps with the simplest plane flying over water. Being locked at 40fps allows my GPU to work between 50-95% with less heat and I can turn up all settings to Ultra with T-LOD at 200 plus turn on HDR10 and everything is silky smooth (yes, I still get the random stutter every now and then and a little more so in very detailed airports/scenery).