Ubisoft made games people wanted to play. It's not a ton of leverage, but more than you can say for Microsoft studios.
What can Microsoft even threaten? No more Fallout 76 and Halo Infinite? Linux is banned from Bedrock Edition? They'll re-cancel the Perfect Dark reboot? Every punishment I try to imagine is like death-by-pillow-fighting.
Even Sony is releasing their games on Steam since they finally figured out that releasing their games for the PC is a more profitable venture than having them be console exclusives. Good luck convincing Microsoft of doing the opposite. Sure, they can make their games Xbox or MS Store exclusives, but it would be an irrational decision even if their end-goal is nothing but profit, since exclusivity clearly will lose them more sales than they can earn back in not having Steam be a middleman.
What can Microsoft even threaten? No more Fallout 76 and Halo Infinite? Linux is banned from Bedrock Edition? They'll re-cancel the Perfect Dark reboot? Every punishment I try to imagine is like death-by-pillow-fighting.