I for one am looking forward to this — I’d love to use it as my resume.
Why? Because context is powerful. When people are viewing your resume, you want 100% of their focus on you, and you want to present yourself in exactly the way that's best for you.
You don't want to present yourself within the context of another org's branding, site layout, etc, which by definition won't be optimised for you, and also syphons off some of that attention you want focused on you (as the most obvious example, say if the top bar has unread notifications).
The irony is with Github, hosting an HTML resume 'on' Github is possible and really easy already via GH pages. It's what I do :-) https://davnicwil.com/cv/
On the other hand, most profession's do have portfolio's and other mechanisms to share work with new potential employers. For some reason developer's seem to think a hiring decision should be made entirely on a a handful of 1 hour interviews conducted in a single day when their work will usually have massive direct impact on the companies product.
I think there's mostly positives to this and some downsides.
As opposed to... some generic profile on a central site? I don't think that is a substitute to actually talking to a candidate.
But what do I know? If I understand sites like HN correctly, talking to a person is not a good way to discover whether he/she has any skills, so maybe this is better from a recruitment standpoint. But I'm not going to create a personal profile there. For the simple reason that the words 'personal' and 'follow our format' don't go together in my mind.