This is hardly a win -- even the most optimistic appraisal can only call our accommodation of UEFI as bare breakeven.
Why? Because we have preserved, to some extent, the *possibility* of installing GNU+Linux on new systems, but certainly the difficulty level is generally harder -- and the percentage of "broken" systems much greater. And the catch-up time during which these issues are ironed out and distributions gain the ability to install or be run live is filled with impediments which will simply convince many that the pain is not worth it. And each casualty is one less person who can participate in the free software camp.
I spent the better part of a day and a half configuring a new high-end workstation which had a preexisting UEFI Windows install, but which had broken legacy boot in the BIOS. And that by a major manufacturer (HP).
My project of easy live-boot sticks for my students in an astronomical computing class will have to be kept on hold until this situation stabilizes, simply there's no maturity to any solution yet that would promise that it would "just work" on the bulk of the random laptops (including Macs) that my students might bring.
Who wins from this fear, uncertainty, and doubt? That should be obvious.
And that's why they keep playing these games. There will be more.