"Hidden navigation on http://orangesprocket.com/ is a design decision." Auto-playing midi music is also a design decision.

I agree, calling it html5 is a bit off, but the complaints are justified.

You would be surprised how may designers dismiss basic usability concerns by saying something along the lines "this is an app, not a website".

Every wave of technologies carries a certain culture with itself. A lot of the things in the list are quite characteristic of HTML5 culture. I agree on 404s, though.

I was also thinking what a 404 has to do with design decisions. "Oh, and we'll put a link here that goes to a 404, that's popular these days!"