Ideally, our API overview pages ought to have a specification table box on them, and in many cases we have them. The problem is that because we don’t have a concept of “this API overall” in BCD, you have to compromise, often by picking an important or the most important thing in the API and using that.
It would be nice to have a way to state the compatibility in general this way for overview pages, either as a simple “it’s there in this browser and this one but not that one” sort of way or as a more intricate set of supported vs. unsupported subfeatures. I don’t really know which is best (and really am not all that strongly aligned one way or another), but having a responsible and standard way to do compat tables on overviews would be helpful.