I'll speak for my parents, who are in their 80's and enjoying a modest lifestyle.
They didn't buy a house with virtually no money down as soon as they were married. They rented for a while, saved up a decent down payment, then bought a modest house (about $11K in 1960), reared three children there, and lived there until retirement.
When I was a child, my mother sewed all our clothes, we ate out maybe once a year.
We took packed lunches to school because it was too expensive to buy the school lunch (which cost 25¢ at the time). Our dinner treat of the week was the Sunday pot roast.
Our vacations consisted entirely of traveling to see relatives. No trips to Disney, or HI, or condos at the beach.
We bought used cars and drove them until they literally fell apart. We were the last on the block to have a B/W TV and the last to have a color TV. In fact, we were always the last to have any kind of newfangled technological gizmo.
If something needed fixing around the house, Dad did it.
We didn't have tennis lessons/art lessons/golf lessons/summer camps/etc.
Our activities were the ones offered for free in school, the community, and church.
Mom stayed at home, but when it was time for us to go to college, Mom took a job and that's how our college education was paid.
Compare that lifestyle to the lifestyle of any young adult you know.
Yep. Additionally, our annual vacation was one daytrip by family car to the beach. The family car was used by Dad to get to work with the exception of that one day.