Sony didn't announced Resume and other feature Microsoft announced. Xbox Series X was playing and resuming 5 different unoptimize games with improved Loading times, you didn't need to restart the games. It's an innovative feature.
While they haven’t announced the specifics yet it does sound like the PS5 is trying to do something similar to quick resume. There was a thread recently about PS5 letting you boot directly into certain/specific instances of any given game, or something like that, which seemed pretty cool too
Quick Resume looks great, for sure
Hopefully both OS’ have lots of fun tricks for us