Hmm, I wasn't aware that the Ultimate edition was any different on PC. I thought all those optimizations were for the PS5 and Xbox Series X|S?
It's all a bit of a confused mess on the PC. On Epic, the ultimate edition is the standard version + the DLC. Straight forward, clear cut. However on Steam they only sell the ultimate edition, but a lot of people (me included) got Control through Humble Bundle. Depending on when the bundle was redeemed it would have said ultimate edition or standard, when redeemed on Steam it claims to be ultimate edition regardless, but it doesn't include the DLC, and it also seems to be an old build with numerous issues. (There's a mountain of reddit threads covering it)
So they've cheaped out and given an old, standard version that's merely called ultimate edition so they can make more money selling DLC? Erm... well, the DLC is no longer even available on Steam.
I don't know what they were trying to achieve, but as you can see it's all very straightforward and not confusing at all.