For non-free fonts, prohibiting embedding is often consistent with the
license, so the two lintian warnings often don't really apply. On the
other hand prohibiting embedding is particularly user hostile so Debian 
should probably try to discourage it. On balance I think the right
solution is to downgrade the embedding tags to either info or pedantic
for non-free packages. The openboard-extras-nonfree package is already
overriding this tag, probably due to the warning vs pedantic level.

truetype-font-prohibits-installable-embedding
opentype-font-prohibits-installable-embedding

Hi Paul,

I too would like to see variable visibilities, but we do not currently
offer them. The traditional solution has been to introduce new tags.

Maybe I will take it as an opportunity to give the matter some thought.

Kind regards
Felix Lechner

Splitting the tag up would also allow having different advice for
packages in main vs non-free, which I guess is not an option for a
single tag either, so splitting them is probably a good idea anyway.