I don't understand it in too much depth, but it seems to have to do with the faster response time of OLED. It makes the transitions from one frame to the next more abrupt. When I'm playing at 30 or 40 fps it looks like something is wrong with the screen. It's literally unplayable for me. What I'm not sure of is whether I would get used to it if I subjected myself to it for long enough. These TVs have technology built into them to attempt to mitigate this, but as I understand it this has the side effect of adding input latency. The tech is called black frame insertion. I haven't tried it.
this is me. I mean, you can just google "why does 30fps look worse on OLED" and you will get many articles explaining it.
I'll legit never forget when I first bought my OLED, I thought to myself "oh boy let's whip out Ghost of Tsushima, that game looked awesome, I bet it's going to be great!", booting it up on my PS4 Pro...and I was flabergasted, I couldn't stand it, it was night and day between this and my old LCD. Then I started trying more 30fps games and really struggling with any sort of camera movement, and reading up on it to find out it's just much more noticeable on OLEDs for whatever technical reasons.
I remember of the many games I later tried on my Series X (or was it on my XB1 still? either way), the only that didn't bother me was Arkham Knight, which has the MOST aggressive use of motion blur I've ever seen in a videogame, and I guess that's why it "hides" the camera judder of 30fps I dunno.