HTML Design Principles is one of the things I'm most proud of writing (along with co-editor
@annevk
and its other contributors). Some of these principles have so won the day in web standards that it's hard to believe they were once controversial. For example, there used to be a major constituency _against_ supporting existing web content.
Some of these directly inspired the W3C Technical Architecture Group's Web Platform Design Principles, which are applied when the TAG reviews proposed web standards.
It's more comprehensive, but IMO less well-written - a bit too verbose & bureaucratic.
Still, it's great that we have such a significant shared body for principles on how the web platform should evolve. And on a higher level, I'd also cite the Ethical Web Principles: https://w3ctag.github.io/ethical-web-principles/
And the Privacy Principles: https://w3ctag.github.io/privacy-principles/
