Possibly they don't mean anything evil here, but as I said, MS aren't free of lock-in nastiness yet. Otherwise they would have joined the Vulkan working group already. They simply didn't earn trust in that area.
Developers' efficiency. But MS understanding of "gain" is a crooked one. They want to prevent developers from releasing anything for the competition, so they use tools to make it harder (lock-in tactic). Or if they can't prevent it, they want to tax it (i.e. to make it more expensive). It is clearly crooked.
And I don't mean just to make Vulkan better. I mean MS starting supporting it instead of DX12. Same AMD can produce Vulkan support for them for Xbox quite easily.
Same as supporting standard HTML instead of ActiveX and Silverlight? If not using lock-in is shooting in one's own feet, you have some strange notion of what's normal.
Exactly same thing here. They used DX to lock 3D graphics into their platforms.
Whether they lost deservedly or not, lock-in is always a crooked practice.
See my other comment[1], that with DX12, it's more clear that MS are doing it for the sake of lock-in. Problem with it - it doesn't compete on merits on Xbox for instance. Because it's the only thing supported there.