Easy: as an engineer, my father in his late 30's could support my mother being a SAHM, three kids, buy a 120m² (IIRC?) small house with a garden, and all the modern commodities (well, safe for electronics that didn't exist at the time).
Nowadays, I'm also an engineer in my mid 30's, and I can just buy a 40m² flat. Never talk about kids.
The houses I grew up in are more affordable today then they were when my parents bought them. Inflation adjusted price is about the same but interest rates were far higher.
Criminality rates are roughly stables since the 80's (https://www.alternatives-economiques.fr/sites/default/files/...), French cities in the 80's were definitely not ‶crack-induced hellscapes″ (and if they ever were, it's definitely now, just visit Paris or Marseille by night), and safe for pollution, I don't think they were notably worst or better to live in than now.