For all your 'objectivity', you think DX12 is great because its made by MS, and you also think UWAs are great because they are also made by MS. Even though if what you actually believe in is platform agnostic APIs you would support neither.
Hmm, there's an awful lot of projection going on there... I could easily also say you believe that everything MS does is bad and therefore if you see "MS" you instantly go into attack mode.
If you're genuinely interested in a discussion on this rather then I find it all quite fascinating: MS are evolving from a company where everything was on Windows, to where they got left behind by the smartphone and tablet revolution - and now they're trying to play catch up. The company has embraced a way-wider, way more open stance in many areas (lots of Open Source releases, apps on iOS and Android, Unix on Azure, for example) - and yet in other ways they're still a platform holder that is focussed on primacy the experience on their own platform. Sony don't get grief for not making their APIs available on PC or on other devices... and that's fine IMO, it wouldn't make any sense for them to do that... so why should DX be any different?
I've got no issue with saying "Vulkan is great and makes more sense for targetting lots of platforms" - that's a no brainer. What gets tiresome is the predictable "MS did it, therefore it's bad" agenda that some posters have, whatever the topic, whatever the competitive situation, and whatever the wider context.
On UWP - from a technical point of view I like it, but I'm an enterprise software dev so it makes perfect sense for me. As a game dev technology I'm neutral-to-positive on it depending on how it works in practice. I simply don't have the data to say whether it's better or worse than Win32 for gamedev, however intuitively from what I've used of Win32 and what I've seen of UWP it's a far more productive API because it's designed with a lot of modern thinking and patterns and can eject a lot of the Win32 legacy bloat.
The UWP/Store combo is a fascinating one for me - all of Microsoft's competitors - the ones who are eating their market share - have closed platforms and a sole store operated by the platform holder. I don't think MS will ever go this route - but they have to provide
something in this area. That's just common sense... otherwise in ten years time Windows will be dead and gone - I can hear the cheers, but ask yourself which alternative will take over? (and no, it won't be Linux).
So please don't try and pigeonhole me into some kind of cheerleader for Microsoft. As I've said before on here I won't come out and openly slag them off, but that works both ways - I don't tend to be critical of Sony et al when I think they're doing something stupid. I just try and comment on how I see things, without the hyperbole.