I disagree strongly that Xbox’s issue is PC day 1 support, and I also disagree that PlayStation fans would just go to PC to play COD in the event of exclusivity. There are huge number of console only gamers who simply will not buy and PC capable of playing games and never will.
Xbox’s biggest problem right now is lack of product differentiation vis-a-vis PlayStation. There is basically no difference between a Series X and a PS5. So if you switched to PlayStation in 8th gen, what incentive do you have to switch back to Xbox?
I think Xbox needs more than just exclusive content to get people back into the ecosystem. The next console needs to do something unique, or come in at an absolutely killer price, or some combination of the two, in addition to the exclusive content