Per these guidelines, packagers should ask upstreams to include license texts
in tarballs in case they're not included.
I think it would be useful to have a document blurb targeted at upstreams that
would document why this is necessary, how does it benefit them, and how to
include the texts in case they have doubts or questions. Packagers could then
just give a link to that already when requesting addition of the license
texts. Could someone add such a thing to wiki, along with packager
instructions how to use it/how to ask upstreams to include the license text?