Disposable income of the 70s was a tiny fraction, many orders of magnitude smaller than the disposable income of 2024.
In addition, houses in the 1970s, 80s, and 90s are not comparable to houses today. Modern houses and cars should cost a lot more because they offer a lot more.
All I am saying here is that the picture is a lot more complicated and nuanced and needs a more detailed evaluation than a simplistic scaling factor into the past.
The cheap housing of that era (even discounting the lead paint and asbestos-based insulation) might not be something you would want to live in today.
Housing is more expensive because people value it more than in the past.
They might value it more because housing is much better than in the past. That could be a simple explanation to what we observe.