$45,000 in 1972 is equivalent to $360,000 in 2026. $9,000 in 1972 is equivalent to approximately $72,000 in 2026. The minimum wage in 1972 was $1.60 per hour, the median wage was about $3.80 per hour. That $20k in cash for your car is about $2500 in 1972 dollars, which is equivalent to what a similarly used sedan cost ($2,000-$2,800).
The more you dig into inflation adjusted figures, the more you’ll notice that the economic situation faced by young people today is roughly equivalent to what young people faced in 1972, which on the bright side is not worse, but it’s also not better. The problem is a stagnation driven by a monetary system that robs wage earners of progress and of sharing in the productivity gains which had historically boosted wages.