Nothing exists in a vacuum.

I'm not a fan of Chrome, or some of the choices they made for ChromeOS, but if they're willing to provide "proprietary" hardware APIs, that are fully documented and open-source, and can be used free of charge, and free of mandatory centralised control mechanisms like on iOS, then I'm all for it.

Mozilla had the opportunity to do the same with Firefox OS; but, of course, now they don't quite have the resources to do that anymore, so, instead they get to tell us that we cannot have nice things?

The process is via W3C, or in agreement with other browsers vendors, otherwise it is Internet Explorer all over again.

But which other browser vendors have the capability to deploy these things?

For example, who else can deploy WebNFC?

Mozilla, for one, cannot, because Apple won't let them.

There are other OSes out there where Mozilla doesn't do WebNFC, exactly because it isn't a Web standard, it is a ChromeOS feature that Mozilla doesn't agree with.