Well of course he doesn't think DX12 is as enticing as what he is working on. I am sure Reggie thinks the Wii U has the best holiday lineup, and I am sure Jerry Jones thinks his team is the most exciting and most worth buying tickets for.

Since when is this the one and only alternative? I think you should take a look at the pick in OP and read what is says.

Valve is using Linux for it's operating system, of course they're not going to support DX12.

Windows 10 is pretty amazing, the apps are kinda useless, but it really dusts W8 and outdates W7. If its security issues you're worried about, get DoNotSpy10

Steam Machines and Linux are irrelevant to gaming, if Vulkan wants to stamp out DX12, it needs to be faster and easier to develop on.

I mean cross-platform is the most efficient, but considering the state of internet backbone, its obvious that convience beats out efficiency every single time.

You missed the obvious example.

Security is my main concern. Thanks for this link, I'm gonna monitor for some time if this remains working and there is a chance to block MS from invigilating me.

A second issue is older games - do they still work on W10?

The only gaming issue I've had so far are with games that need jap locale, but their are workarounds. Emulators and old games work fine for me.

valve still has a BIG part of its revenue on windows (and will have as long as windows exist). Vulkan is on win7/8/10 too.

Well since PS4 isn't running a Win10 variant it devs are going to have to use something other than DX12 to get their games onto the biggest selling console of the generation. And if Vulkan is the best alternative, which no one seems to be arguing, it seems like it doesn't matter whether DX12 is best or not, devs are going to have to use Vulkan regardless if they go multiplat. Given Vulkan will also work with Win10 and with Win7/8 it seems like a no brainer for devs to prefer Vulkan because that gives them the maximum number of platforms on which they can release games.

If Vulkan can deliver legacy and new PC+PS4 (and Linux for good measure) an a fairly dev friendly way then even if DX12 is a bit superior the force of numbers in favour of Vulkan could push DX12 to the margins. MS might quickly decide to update DX12 to work with Win7/8. Shutting out those older OS's might prove to be a mistake. Probably would have worked if Xb one didn't have just half (almost) of PS4's install base. If Win 10 and Xb one were major players then MS could have been pretty forceful with DX12, but they're not really in that position.