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Jeez... won't we be using HTML 10 by then? No wonder browser makers make their own standards if it takes so long for the w3c to do anything!
It takes a long time to do things properly. It would have been quicker if "someone" (hello, Microsoft and Apple!) didn't keep sabotaging the process.
Also, just because the final recommendation isn't out until 202x doesn't mean that the spec won't be usable before that. The more it matures the better the browser support will be, and that will happen many years before the final spec is out.