Cleaning up specializations of body elements

Hi, I'd like to recommend another DITA 2.0 "cleanup" item, this one for specializations of <body> like the <conbody> and <refbody> elements.
It requires a bit of history though.
In DITA 1.0, all body elements could not be filtered.
We didn't allow attributes like audience.
I have a vague memory that they were treated like titles, basically "you should not be able to filter this because every concept should have a concept body."
In DITA 1.1 this was updated for <body>, but not for specialized elements like <conbody>.
As of DITA 1.1, the body element used all of the common / universal attributes, including the filter attributes.
Conbody, taskbody, etc continued to drop the filter attributes, even though the elements themselves were optional.
That continues today.
Most specialized body elements have a confusing attribute list of "All the universal stuff, except for the filter attributes for unexplained reasons."
This seems like a really old oversight we should clean up in DITA 2.0 -- for any specialized body element in the standard grammars, we should update the attribute list to match the attribute list for body itself.
Thanks, Robert