I can not see a performance drop since SU9 with the airplanes I fly, e.g. DC-6. Also a short test-flight with the A320neo show me no strange things.
May be the common thing in that topic is these FBW Thirdpary Mod, or a ‘function’ which this mod use. This is also on what the common “coherent…” points in you screenshot.
Screenshot: A320neo ( I disabled extra my vsync max to see what I get : same cpu i7-8700K, 2080ti, 3840x1600 ) ( only OC I use is sync all cores: I not increase freq. like you 
)
so, I can not see any kind of issue, fps are fine.
PS: still be carefully with your OC and windows restart from time to time would also be good. And thats your old topic about, or ?.. was that fixed ? 3-10fps over the ocean with perfect blue skies. Machine can do 30-50fps