The build more thing is in urban areas to accommodate urbanisation. Coming to think of it the 49 Euro ticket might actually reverse some of that because there's tons of smaller towns, sometimes villages, with proper train connection to the next large city. Low prices drive usage which prompts higher train frequencies which, infrastructure permitting, takes even more pressure off the metropolitan housing market.

That said urbanisation isn't in itself a bad thing -- it makes a lot of sense for a lot of reasons to not have a gazillion tiny villages, it'd just be another form of sprawl. Here in SH, if every train station we do have had a small urban core around it surrounded by village structures in cargo bike distance and then long stretches of fields and nothing, that'd actually be quite nice. The state was very good at doing that in the Hamburg metropolitan area, focussing development on a couple of axes radiating out from Hamburg but it should become more of a general pattern.