a. As far as we currently know, Sony only has 3-4 big exclusives for 2021, Horizon: Forbidden West, Ghostwire Tokyo, Deathloop and Demon's Souls remake (assuming it isn't a 2020 game). Xbox will have 3 big games for 2021 most likely, Halo, Flight Sim, and Forza Horizon 5, possibly more since they still have a 3rd 2020 show and E3 2021 where they can still announce more 2021 games.
b. As far as I know the only games on my 2021 list that are already released on PC are Flight Sim and Bright Memory. Bright Memory is in the 500k-1m range on Steam Spy, which isn't bad at all for a game developed by 1 person. Flight Sim just released and according to an insider is selling on pace to sell more than 1m in the first month.
You're putting a title you made-up to prop-up XBox's barren launch, while removing stuff Sony announced.
This is deluded fanboyish behaviour