This is true for the gamma shift issue only. But, for me its not a big deal to be honest. I went from 120hz to 60hz and didnt notice any difference in gamma.
The biggest problem is the gamma flickering, which happens when you get a small spike in frametime (stutter), and the higher the framerate is, the worst it gets. I know this by doing a lot of tests in my system (RTX 3080 + LG C9)
Yes and no. Both issues are tied together somehow.
OLEDs always had issues with near blacks. And they of course still have.
Back in 2018 or so LG rolled out an update to disguise the near black flashing issue
on those TVs. They introduced some sort of "black crush" to make this issue less noticable.
But with the gamma shift introduced by VRR this method becomes useless. Because you now see
see issue again. Even without VRR you can spot near black flashing on OLEDs. Just make sure
you are using Gamma 2.2 or lower. In a dark room those flashes in near black areas should be really easy to
see. Especially with heavily compressed content.
It is actually quite interesting that you are experiencing the exact opposite effect on your TV.
I also have a C9. And for me and other people I know it is always less noticable the
higher our FPS are.