It's similar to how you don't want companies to have your personal data, even if you trust them "100%". When money becomes a problem, or a solution, you'll be their last priority.
Some of the news about Windows 10 would be unthinkable a few years ago. Priorities change, and this company in particular has a history of being extremely hostile.
But that’s not saying that Microsoft is 100% trustworthy or that they will never do anything bad ever again. I’m only saying that the “sinister plan” for this one particular software component is to make Windows more useful to Unix-land developers, to try and get them to buy Windows PCs instead of the usual MacBook Pro. Notice how that explanation still assumes Microsoft is still doing it for their own financial benefit, but doesn’t require an agenda to destroy Linux. They have realized that this isn’t a zero-sum game.
Nobody at Microsoft ever had a committed ideological opposition to Linux, it was a pragmatic decision based on what they perceived as a threat to their business. That certainly doesn’t negate the damage of all the shit they pulled, but it does mean that it is highly unlikely that they’re going to reverse course and start extinguishing Linux for ideological reasons now that they’ve figured out how to make money without Linux being the enemy.