I suspect mostly second. For example, in Soviet Union housing was a huge pain point. Young (and not so young) residents who did not live with their parents live

I suspect mostly second. For example, in Soviet Union housing was a huge pain point. Young (and not so young) residents who did not live with their parents lived in dorms for years (sometimes 10+ years) while the queue for their own apartment slowly moved on. Those postcards may be showing something to look up to only several short years away. I think.