It looks like the link for recommended licenses in the latest documentation is broken. This links out to Cabal Distribution.License but those docs don’t seem to have been built recently.
The Hackage operators do not want to be in the business of making judgements on what is and is not a valid open source license, but we retain the right to remove packages that are not under licenses that are open source in spirit, or that conflict with our ability to operate this service. (If you want advice, see the ones Cabal recommends.)
Going back to 3.4.0.0 provides an active link Distribution.License