Because that's not how videogames in 2023 (or the past ~decade plus) have worked.
You need, at a very minimum:
— login system that also works with consoles
— persistence for users stats (maybe not for some kinds of games)
— matchmaking service (which really wants a persistence system for SBMM)
— make sure your systems aren't actively being exploited (you don't want to accidentally run a botnet)
— make sure nobody is "hacking" or modding the game (what's the point of keeping the severs up if they're filled with aimhacking bots)
— monitor the services to make sure they're up
— potentially patch the games on multiple platforms if you need to make a backwards-compatible change to fulfill any of the above.
— also potentially update your games if the console vendors make changes to their stacks
I agree that it sucks that the services are being shut down without any alternatives being provided, and I wish there was a way to force the publishers to support them for longer or provide an OSS servers options; but it is definitely not "free" or "easy" to provide these services for years.