Earlier quoted context omitted.
> W3C decided to deprecate HTML in favour of XHTML. Most of the web quickly moved to XHTML. In some parallel universes, yes. Even if so, there's also the fact that XHTML wasn't updated itself with features people needed.
What features? If you're referring to "features" in the HTML5 spec., like canvas, webgl, geolocation, DOM etc. they were separate specs, which WHATWG lumped into one monolith (though they're mainly JavaScript APIs, and aren't directly related to HTML). They were being worked on separately to XHTML, and still work fine with XHTML to this day.
For which I could not care less. Whether there's a big spec for HTML5+JS APIs, or 20 different specs, is a bureaucratic concern, not a concern to the developers or the end users.
W3C might had them "neatly" separated, by it also haven't moved them notch towards completion and release for more than a decade.
I've used and worked for the web before W3C, in its heyday, in its long decline days when we waiting a decade+ for some progress, and after it become irrelevant. Now it's a way better situation.