I would really love to see this happen. That would make me possible also to put a non 0.x.y version for markdig, as I have to wait that the specs are completed otherwise that would bring significant breaking changes.
Regarding the problems, from a practical perspective, I think that the current spec is perfectly fine and that’s what is most important. And as stated in the discussion in Beyond Markdown, if we really wanted to make this specs easier, this would require to fork/break entirely from the current Markdown that is commonly used elsewhere. CommonMark is the only standard available today, and if GitHub might not be the only user of CommonMark 0.28 now, it is such a significant big user/player that I would not expect the current CommonMark specs to change significantly.