There are now only 4 properties from AllHTMLAttributes that do not exist in HTMLAttributes & all the per-element interfaces:

• contextMenu/contextmenu
  • Was added in the original batch of types 6 years ago and marked deprecated then. Since then, the MDN page documenting it, which we had in our deprecation comment, has been removed entirely. Seems like a good candidate for removal.
• icon, manifest, radioGroup
  • I can find no mention of these attributes/properties existing and all were added in the original batch of types 6 years ago. As such, I'm guessing they were mistakes.
  • There is, however, a radiogroup aria role. I'm guessing that's where it came from at least.

Now this doesn't quite guarantee all types are correct, because of the split interfaces we may still need to copy types to elements that are missing them, but all types do at least exist somewhere in the new set. Additionally, we do appear to have about 25 new prop/attr types as well that we were missing in core previously.