notes from the df article on PS5 modes
on average the performance mode is ~ 1800p locked 60 fps
"Quality mode renders at a full native 4K while performance mode instead uses dynamic resolution scaling ranging from 1440p up to 2160p. On average, pixel counts reveal that it spends most of its time around 1872p. What's new this time, however, is the inclusion of TAA with upsampling. This TAAU solution helps even lower pixel counts appear suitably 4K and as a result, image quality is greatly increased over the prior game. The two modes look very, very close."
or can unlock and get 1440p at ~ 80-90 fps average
"The high frame-rate mode basically removes the 60fps cap and bottoms out the resolution at 1440p, allowing the frame-rate to reach for 120 frames per second instead. The reality, however, is that we're mostly looking at a performance between 80 to 90 frames per second in most scenarios."