Because Microsoft is smart thinking long term and doesn't care about an outdated model of selling consoles anymore, as it sees the future revenues comes from owning valuable IP and monetizing that instead on all the gaming platforms, regardless on which hardware you use to paly it: Xbox, PS5, Switch, Steam, iOS, Android, Linux, MacOS, tablets, smart-TVs, etc., they don't care, they'll gladly take your money regardless if you have an Xbox or not.

They're slowly dethatching themselves from the console HW and moving to selling services the same way the detached from Windows and Office as the core products and made more money selling O365 and Azure subscriptions including their arch nemesis Linux.

That's why they keep selling CoD to the competitor's Sony PlayStation instead of making it an Xbox excusive like Sony and fans feared they would. People, and Sony, still don't get it, that Microsft's new business model is monetizing IPs and services, not selling more console HW thanks to exclusives like the old days. They'll probably make more money form Candy Crush than Sony makes from Last of us on PlayStation.

Holding on to the "console war" ("muh console sold more than your console!") is just silly and outdated. The big money is now gonna be in IP and services, not selling console HW, and Apple also knows this which is why it focuses more on new services for existing customers (ApleTV, credit cards, SOS satelite, etc) and less on selling more iPhones to new customers as the hardware market is already saturated.

Nintendo will outlast the Xbox, but Microsoft will outlast Nintendo.