I would also suggest adding this information to all elisp files on
EmacsWiki. Perhaps this can be done automatically
I would advise against trying to guess compatibility like
that. Let library authors determine and specify the compatibilities
explicitly. Else assume nothing.
I have asked for that before, but nothing happened. That
means that the burden is now on the users.
Maybe something like this can be used then:
1) Announce that an automatic change as above will be made unless
package authors (or someone else) adds the Compatible label.
2) Do the automatic change after some weeks.
This is a discussion for Emacs Wiki, not here.
Personally, I disagree with any automatic messing with source code contributed
to the wiki. Please leave the source code as its contributors wrote it.