[llampx]

blablacar and mitfahrgelegenheit.de were built primarily for poor-ish people and students. And these are sites/apps which have a good UX for the purpose of finding and booking rides, or offering rides. So I can't agree that you can't get uni students to use something like that. Maybe in the US where seemingly everyone has a car or doesn't need a ride very frequently.

Suggestion: try going on blablacar and booking a ride from Berlin to Munich, or Paris to Lyon. I think you'll find it quite straightforward.