I've worked with many developers. From the biggest 1st party AAAs to 1 person indies. With something like game pass, you have to look at different numbers. Sales have never meant people actually enjoying or even playing the games I've worked on.
If everyone played the games they bought on steam sales for pennies on the dollar, some of the devs I worked with would have lost a ton of money on support costs alone. I know there are hundreds of thousands of copies, maybe millions of copies, of games I've worked on that sit unplayed or barely played in people's digital libraries.
Less than 1/2 of Witcher 3 players saw the ending. Think about that, less than half of the people who played Witcher 3, who plunked their money down on it, stuck through to the end.
If your game connects with someone, they will play it. Maybe a lot, maybe over and over. Some will try to explore every nook and cranny. That's the metric of success on Game pass. Engagement.
If I'm proud of a game, and I want people to be able to play it and love it, I want to remove every barrier of entry. Dropping $70+ to play a game is a barrier to entry. Dropping $5 is a barrier to entry if I'm not sure if I'm going to like it. If microsoft have found a way to remove that barrier of entry, and sustain development costs at the same time, then I am all for it.