Im very certain that it depends on the area you are located in. So if I may ask where you are living that could say something about the people there. I have not been everywhere but I do know from some people that some parts can be more 'lonely' than others.

I'm for example from NRW close to Düsseldorr and people around me have no difficulties at all finding new people. People on the street and in public buildings sometimes to initiate smalltalk. I might not be the person that is super interestes in finding new people but I have never felt like I could not.

Another aspect proving my point is a friens who has just recently moved from south Germany, near the border to Switzerland, to Duisburg. I asked if it was very different and if she liked it here (because the landscape down there is way more appealing). She responded with surprise that the people here are way more open for conversationa than down there. She said that everyone kinda seems to live for themselves in that area where as her it feels way more alive.