Not sure I have those older US TV legacy frequencies to try, and I’m not sure why they’d be better than 30 or 60. I do note your desktop and active signal mode are both at refresh rate of 119.88Hz so that is why you need the legacy rr fractions of that frquency.
I just know that 1/3, 1/2, and 1x tv/monitor refresh rate at native res can lead to some very fluid experiences in FS. And I’ve seen this across several different setups now. And with both 60Hz and 120Hz rr’s.
It’s certainly worth people experimenting with.
I suspect it makes for easier timing of each frame that is generated by the graphics card so lessens the workload and latency.
You don’t often see people mention it, but it seems to have quite an impact on sim smoothness & fluidity when moving views around especially for things like panning around the view in the cockpit of a complex airliner parked at an airport gate.