Quick math -
Xbox Cloud Gaming gives you 50 hours for $12. You could game for 3333 hours to equal the Xbox Series X in price ($800). Say you want to depreciate the device over 7 years, that's about 500 hours of gaming a year, or ~9-10 hours a week.
I'd say that's a pretty reasonable limit for a low volume, casual gamer.
That heavily assumes MS does not increase the price, which has been proven to be false when they increase Gamepass price in the past.