I think a good argument can be made that the standards somewhat move a bit too slowly to add things? (Or, conversely, can be too eager to add some features.)

I think a good argument can be made that the standards somewhat move a bit too slowly to add things? (Or, conversely, can be too eager to add some features.) Probably a bit of a struggle between de jure and de facto. It can be frustrating, as many of the more important standards out there were de facto. We try and pass them off as otherwise, but "div/span/XmlHttpRequest" and plenty of others were in practice before they were part of the standard. None of which is to excuse players from not at least accurately advertising what standard they support. There should be consumer protections involved on that. And I think a decent argument can be made that stricter compliance can be expected from the big players.