It's already been stated by analysts that Game Pass actually boosts hard sales, doesn't hurt them.
Is that why Gears 5 sales are like historically bad, compaired to the 3rd or 4th game?
Maybe it doesnt hurt that much like a year down the line, but day and date seem to have a negative effect.
(physical and digital sales tanked compaired to the last games, and Phil Spencer used jargon speak to count a digital download on gamepass as a "sale", to claim it sold better than the 4th)
Gamepass makes sense if a game is already selling badly (past its peak of sales) and has ingame micro transactions /dlc they can sell you.
Then getting it into more players hands even if free, can be lucrative.
However claiming it doesnt hurt sales is bullcrap.
Necro-bump this 2020: http://gamrconnect.vgchartz.com/thread.php?id=229249
Bumb in 2021: http://gamrconnect.vgchartz.com/post.php?id=9047071