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They're still trying to do their own thing, regardless of where the rest of the world is going.
Now, is Microsoft a different company and more open to open source? Yes. I have an open source package to control Azure (and they support Linux on it). They've been supportive of the local OpenStack meetups. They're a bit less hostile to dual booting systems. The costs and licensing have come down a good amount. The Xbox 360 is a really nice gaming system. They have way better backwards compatibility than Apple.
But they're still at heart the same company. The UI they started in Windows phone made it to the Xbox, then to Windows 8. That kind of UI just doesn't work on laptops and they should have figured that out. The Xbox One was going to squash game resale and borrowing. Live is a pretty big disaster, and every update to Windows 7 tries to include some new version of Bing, hoping I'll install it.
Can I install different browsers in Chrome OS? Don't know, don't care. Chrome OS is a small fraction of the laptop market, and my Android devices have various choices for browsers and most importantly, I can set the default browser and have that service every http link I come across, same with most other apps.