So games like Hi-Fi Rush, which is incredible mind you, gets a very small bump in revenue from being the hot Game Pass game for a month, then it falls off a cliff when everyone moves onto the next thing. Poor Redfall had it even worse since it launched so rough, it never had a chance. This system was fine for a while when Game Pass was growing like gangbusters, but now it's slowed way down and the amount of revenue it's attributing to games isn't keeping up with the budgets to make them.
So far, the big bets on driving new subscriptions (Redfall, Starfield) haven't spurred near enough growth, and there's not much on the horizon that is likely to restart the momentum. The best bet is COD, but do you really risk the guaranteed sales revenue that franchise brings by putting it on Game Pass on Day 1 and potentially lose massive sales? I don't know what the plans are, but either you put it on Game Pass and lose money, or you don't and the subscribers revolt because they think that's what they signed up for."