Launch week? Not much, unless you really like both Gears and XCOM and are therefore interested in Gears Tactics. But before the end of the year the first 2 episodes of Remedy's CrossFireX campaign and The Medium are set to release, one is a AAA exclusive and the other a AA, both are pretty cool. Maybe not huge system sellers, but Xbox doesn't need huge system sellers to sell out this Holiday, I mean the day one preorders sold out in less than an hour in almost every country, in less than 10 minutes in some countries. Consoles always sell out at launch, even Xbox One had the 3rd biggest console launch of all-time (only behind PS4 and Switch), and it had just about every factor imaginable going against it (higher price, weaker specs, negative PR from the poor reveal, etc.). And Series S should be huge this Holiday with parents and grandparents buying Christmas presents, thanks to it's low $300 price tag. MS just needs to get a system seller out in early 2021 to keep the sales strong into next year, be it Halo Infinite or something else.
Also plenty of people buy for future proofing. I'm buying at launch mainly to get better graphics on the 3rd party multiplats like Cyberpunk, AC Valhalla, and Watch Dogs Legions, though I plan to play a few of the launch window exclusives on Gamepass as well.
Look i'm not trying to argue for the sake of picking sides or putting one console down. I want all gamers to get the best for what they pay for on launch. I just don't like it that they can't launch a system without a killer exclusive or some small games that showcase next gen. Maybe it's early for devs to show off the it's power, so maybe it's premature for both consoles to release this year. I would much rather see a console release with something stunning, something not seen before to get us excited for next gen gaming.