I love that the technical details tables for all the HTML element reference pages includes permitted ARIA roles, but I think it would be a good idea to add the default role for each element as well.
I often find myself looking for this info but have to go to the ARIA in HTML spec to find it. Additionally, I feel that including this info would perhaps help to educate developers about semantics and perhaps even prevent some developers from adding inappropriate roles to elements that don’t need it.
I’d be happy to go through and start adding this info myself.