PS5 has always had a slight FPS advantage in multiplats. It's due to the higher clock speeds.
The Show: FPS Advantage for PS5
https://www.eurogamer.net/articles/...-multi-platform-first-party-sony-title-tested
" All versions run with an unlocked frame-rate, capped only by v-sync at 60fps. Actual in-game action runs nigh-on locked at 60fps on PlayStation 5, and it's much the same on Series X - just a little less stable. However, it's in the games cutscenes (or 'presentations' rather) that San Diego Studio pushes graphics much harder. Frame-rate buckles on all machines and it's here that we see that Series X occasionally matches PS5, but more often drops harder - by a factor of around 9-11fps."
Avengers: Resolution and FPS advantage for PS5
https://www.eurogamer.net/articles/...arvels-avengers-next-gen-console-head-to-head
" PlayStation 5 can hold its 60fps a little tighter than the Xbox consoles during intense destruction"
Control: Series X Stutters PS5 Does Not
https://www.eurogamer.net/articles/...ltimate-edition-tested-on-ps5-xbox-series-x-s
"Series X exhibits some stutter not seen on PS5 - regardless of it being set to graphics or performance modes. It crops up with the arrival of UI elements on screen and in standard traversal, and can be distracting."
Hitman: FPS Advantage for PS5
https://www.eurogamer.net/articles/...as-a-4k-resolution-advantage-on-xbox-series-x
"Put simply, it's 60 frames per second... with just one exception in our hours of play. In the Mendoza mission set in Argentina, it is possible to see Xbox consoles run between 50 to 60fps around a field towards the outskirts of the level, while PlayStation 5 remains constant at 60fps."
Destiny 2: FPS Advantage PS5
https://www.eurogamer.net/articles/...ny-2-ps5-xbox-series-a-huge-performance-boost
"60fps performance is generally excellent on Series X too, but it does have some minor frame-rate drops from the target 60fps, while PlayStation 5 is slightly more consistent in this area. "
Assassin's Creed Valhalla FPS Advantage PS5
https://www.eurogamer.net/articles/...sassins-creed-valhalla-ps5-vs-xbox-series-x-s
"The key takeaway is that PlayStation 5 is much closer to the 60fps target more of the time, while Xbox Series X can struggle. In fact, at its worst, we noted PS5 delivering a 15 per cent performance advantage over its Microsoft equivalent in identical scenarios."
Call of Duty: Black Ops Cold War FPS Advantage PS5
https://www.eurogamer.net/articles/digitalfoundry-2020-cod-black-ops-cold-war-series-x-s-ps5-tested
"Both Series X and PS5 deliver a great 120 frames per second experience, with no issues at all during the multiplayer mode and only minimal slowdown in the campaign - but curiously for this 120Hz mode, PS5 maintains a closer lock to the target frame-rate than Series X."
Note I didn't include PS4 BC games only true Next Gen releases. This makes total sense given the hardware advantages of the PS5 due to the higher GPU clocks. Having higher clocks on the GPU gives the PS5 a 20% advantage in triangle rasterization, Culling rate, and pixel fill rate.
Triangle rasterization
PS5 - 4 x 2.23 = 8.92 BT/s
XSX - 4 x 1.825 = 7.3 BT/s
20% advantage for PS5
Culling rate
PS5 - 8 x 2.23 GHz = 17.84 BT/s
XSX - 8 x 1.825 GHz = 14.6 BT/s
20% advantage for PS5
Pixel fill rate
PS5 - 64 x 2.23 - 142.72 GPixel/s
XSX - 64 x 1.825 - 116.8 GPixel/s
20% advantage for PS5