25:00 is where he talks about XBSX specifically. He uses 56 cu's for it's GPU and ends up around 420mm2 for the APU size.
The 40CU PS5 die is rumoured to be around 310-320mm^2. It is unlikely those additional 16-20 CUs would take 90-100mm^2 (assuming a fifth gddr6 controler) in the XSX. It's still a guessing game in the end.