Yeah this is a really frustrating. A lot of the transit agencies don't have their schedules on third-party apps, and even the ones that do don't seem to usually release real-time data.

For example I'm in Munich, Google Maps shows schedules but not real-time departures, and the data definitely exists somewhere since their own apps show it. Of course, since this is a random one-off transit agency app, the UX is absolutely atrocious compared to Google Maps.