That is because the job of Game Pass isn't to make money, it is to funnel customers into subscription services and destroy the idea that people buy games from artists.
Game Pass either succeeds and destroys the gaming industry like spotify did to music or Microsoft will abandon Game Pass.
They've already plateaued and basically admitted to it. It's a large revenue stream that's not as large as they thought it would be, so now they're going to coast with it and rely on just being a massive publisher instead.
Renting games and music seems like a bad idea to me, but I am in the minority. Buy a new album once a month for $8, after a year I have 12 albums. Pay that to spotify and I have nothing.
Gamepass is priced more aggressively at $12/mo, but I assume it's a loss so they can eventually raise prices. Even so, if I buy a new somewhat discounted game for $36 every three months, after a year I have four games. With gamepass, I'm pretty sure I end up with nothing.
But I don't think humans are known for long term thinking.
GamePass used to be such a good value, but it’s gotten so overpriced. I’d rather keep the money and spend it on a few games a year I get to keep. Plus, not being available on Linux and/or Steam Deck makes it easier to ignore. Never going back to Windows.