Look, I'm not saying saying we should "trust" Microsoft not to Embrace, Extend, Extinguish if they could - but they can't and they know it, so that's not their strategy. EEE was hinged entirely on the dominance of Windows and IE for the Extinguish phase. They won on desktop, but today most of the action has moved to mobile (where Windows lost completely to iOS and Android) and webservers (where Linux is massively dominant). In those domains, they are no longer the 500 pound gorilla in the room, they're the "hey, fellow kids" oldtimer trying to fit in and get in on a piece of the action. Look at a comp sci class in the last decade, and you'll see 1/2-2/3rds of them with MacBook Pros in their laps, because it compiles iOS apps and it's a *nix so it easily runs most of the same tools as a linux webserver. That's what WSL is about, trying to win back developers. That's why they bought Xamarin and Github. That's why they released VS Code. They're trying to win back developers by meeting them whereever they are, even if they know they are targeting platforms where Microsoft is not dominant and has no hope of becoming so. They're trying to make it feasible to target a linux webserver while developing on Windows. They're trying to make Azure a serious contender for cloud computing outside of the corporate C# world. There's not a realistic scenario where they become dominant enough on those platforms to execute any kind of Extinguish move. And they don't need to - there's still tons of money to be made with just a slice of the cloud pie. I think EEE went out the window along with Balmer and the 'Windows First' doctrine. I'm not saying they wouldn't, but I'm saying they can't and they know it, and they're ok with that.
All this is not to say that there's any reason for upstream to accept any bad patches that rely too much on proprietary code. But in this case, I think the analysis of the underlying motivations for that patch was outdated.
All this is not to say that there's any reason for upstream to accept any bad patches that rely too much on proprietary code. But in this case, I think the analysis of the underlying motivations for that patch was outdated.