Earlier quoted context omitted.
That would be a massive loss, though. A lot of content isn't in HTML5, and a lot of that pre-HTML5 content is precious and valuable. Google has sadly already tossed a lot of that by the wayside, since it often isn't served with HTTPS. I think something like 80% of the sites my crawler is aware of serve pages over plain HTTP. In general, attempts at shaping the web through search engine indexing requirements seems to…
Not so sure older content (like the stuff I wrote in the late 90s to mid 00s) would be negatively impacted, so long as search providers pay careful attention to the tag (or lack thereof). I wouldn't characterize holding people to at least a bare minimum of standards (e.g., title in the head and nowhere else, which has been the rule since at least HTML 2.0 in 1994) as "punishment", any more than dinging them for unclo…
If anything, it seems like the single best predictor of whether a website is a content mill is strict adherence to modern web standards and other "google rules".