Back in the early 70's all my older brothers purchased homes prior to age 24. 2 of them purchased brand new half ton trucks one Chevy one Ford and paid cash. Everybody worked menial jobs. One brother purchased his home when he was 18 and still lives there today.
So when you are talking about purchasing a home, a car, or even being able to just live on a wage, that has changed.
Things
did change a lot after the 70s. I attribute it to the end of Bretton Woods in 1971. I think it took the whole decade for the resulting damage to snowball, and really become apparent to non-rich people. It’s not like they warned the general population outright about how bad things were about to get.
Inflation became more and more significant throughout the 70s. It was discussed constantly! It was a favorite topic of comedians (See old Johnny Carson monologues.)
Every politician promised they were going to stop inflation. By the mid 70s, "shrinkflation" was already a thing. I can't remember when penny candy became extinct - I think it was the 80s.
Don’t know what part of the country your brothers were in, but in my neck of the woods things were not that rosy. As a young person it was not possible to pay rent AND save up money to buy a brand new car with cash, or make a down payment on a house
while you were still in your early 20s. For above-minimum-wage pay, you had to “know” someone (a relative or family friend) that could get you into a higher paying job. This was the case even if you just wanted any factory job with decent benefits, say, at the Ford plant or Westinghouse. (This was once a reliable way to support your family.)
During the 70s the factories had already started closing down. There was no such thing as an "apprenticeship" and if "internships" happened, they weren't advertising for them in the papers. You had to be accepted by a union, so you had to either know someone, or fulfill a quota to get hired. (The concept of racial DEI isn’t new, it just wasn’t admitted to.)
No one remembers that every day, the media was always using terms like “joblessness” and “unemployment crisis”. Of course, I’m from a state that’s always had a lot of corruption and that has it’s effect.
Still, I remember people who were able to buy a house before the end of the 70s (possible for 30+ grand!), were always in much better shape than anyone who tried to do so afterwards, when
home prices started doubling and tripling. Living frugally wasn’t enough. By the early 2000s, you couldn’t buy a condo or half a duplex for under 100 grand. It all became very demoralizing.
And what do you do when you can’t find a job that pays enough to allow you to own a home and raise a family? You go back to school.