Gamepass a service that lets you play games, but GaaS generally refers to stuff like Roblox and Fortnite–individual games that act as a platform to sell you things from. That's where the flaws are. I'm struggling to see the flaw with GP except for the inherent flaws with paying for a revokable license to download games in the first place. At least GP doesn't lie about you owning the games that you're playing like "buying" them from the xbox store does.
I mean, is Netflix flawed for offering movies as a service? You pay a monthly fee to be able to watch a wide variety of shows and movies, but you don't own any of it. It's literally exactly the same thing except for the type of media they offer.