Ah, that explains it!
I don’t even remember enabling Smart Smoothing, I always hated it before. It’s one reason I thought performance looked okay in 2024 at first. I hadn’t flown in 2020 for a bit and I think something had updated in the Pimax software.
In 2020 I get much higher frame rates and it causes the warping when FPS drops from the 50s to the 30s. My settings in 2024 seem to knock out a solid mid 30s enough that the Smart Smoothing looks okay.
To me letting the FPS run 30s to 50s+ looks better than a locked 36 with SS. But I can live with it.
You may want to try SS in 2024 and see. I also had to switch to Pimax OpenXR to get 1/2 rate locking working at 36. On OpenXR it seemed to want to be either 32 or 45.
I’ll try without and see if I notice any difference.