So I guess one of the reasons I wasn't enthusiastic about progressing this was the lack of multi-vendor interest in the approach specced there (of re-using CSS primitives).
However, we should be pragmatic about this. innerText is definitely part of the web and definitely needs a spec. That one is certainly better than nothing, and is in fact pretty good. IMO we should just incorporate it.
In doing so we should probably add some minor guidance to authors on why this is a bad thing to use and that there are better alternatives. We should also give it a dedicated sentence in the acknowledgments (as is done for other things previously developed elsewhere, like custom elements). And we'll need to make sure the non-normative parts of the text are converted into notes.
We should probably define a somewhat-generic algorithm that the innerText getter delegates to, and then we can update the spec that defines