I have found a discussion on Reddit, that the Lithuanian translation was missing on the Live DVD installer (source). Which also reminded me, that Hungarian was missing too in the last Fedora release. So I have checked, and it’s missing in this (beta) release too. What can we do to fix this?
https://fedoraproject.org/wiki/Bugzilla
This is how you can file a bug. As to the larger question of how important are missing languages, I think they should be release blockers if it is a supported and complete translation IMHO. But I am not the decision maker on which languages are available on the DVDs. There may be constraints on media size, etc…
Okay, thanks, I have filed a bug: 2019130 – Languages missing from installer including Hungarian and Lithuanian