Open source has won, and Microsoft has surrendered

Many Linux fans greeted the news that Microsoft is joining the Linux Foundation with anxiety-fueled anger.
For example, spooling through Reddit and my Google+ comment feed, I found these sorts of reactions:
“This will destroy Linux.”
“Trump is elected president and now this…”
“Do people not realize that Microsoft has a strong economic incentive to see Linux fail? … That blows my f***ing mind that anything good can ever come out of this.”
&l