The smoke did not drop FPS, the only FPS drops were on the ps5 when it rained.
I implore people who have a youtube to do this, record yourself doing a 1 min lap on blue moon bay infield.
Do a few doughnuts, grind against the wall, and then do a few doughnuts in the grass and dirt. The enter a replay and watch the video again in the normal gameplay view with the hud on , you will see the pre-patch effects.
On base ps4 the sparks are 99% gone, dust effects from the grass are GONE, and the smoke has been culled back about 75%. This is a huge graphics downgrade, the frame rate does not drop in the replay .