Earlier quoted context omitted.
>- XHTML. [...] Would it kill people to have to close their tags properly? XHTML appeals to the intuition that there should be a Strict Right Way To Do Things ... but you can't use that unforgiving framework for web documents that are widely shared. The "real world" has 2 types of file formats: (1) file types where consumers cannot contact/control/punish the authors (open-loop) : HTML, pdf, zip, csv, etc. The common…
I’d argue a good comparison here is HTTPS. Everyone decided it would be good for sites to move over to serving via HTTPS so browsers incentivised people to move by gating newer features to HTTPS only. They could have easily done the same with XHTML had they wanted.
> We rank valid XHTML higher
It doesn’t even have to be true!