Amusingly, your sibling comment had an alternate proposal that included two features, but did not in any way address the one thing you suggest is missing.
Replacing a flexible standard with a more-rigid standard is really, really hard.
The current standard already accepts a comment line at the top, so in this case technologically it is easy, far easier than most problems. However, getting a consensus from a committee with bike shedding and all that fun (horrible) stuff is very hard.
Replacing a flexible standard with a more-rigid standard is really, really hard.