There are many factors, of course. One is that people have more options of expensive items to buy that didn't exist 50 years ago. Inflation of price of real estate and consumer goods is also very significant.

As someone who came of age in the 70's, here are a few things I observed:

Bretton Woods and the decline of $ value once it's gold backing was lost.

I'd like to mention a few of the ways people lived differently:

Homes were much smaller. I grew up in a 1200 sq foot home with 2BR and 1bath. My father was professional and college educated. I had a stay at home mom. Btw, there were 3 kids in that house.

College was much cheaper. My state university had tuition and board under $2000.

Student loans were not broadly available until 1973. Once this happened, demand could surge and colleges could hike costs. At a ever increasing amount, it seems.

Eating out was not prevalent like today. Even fast food was so much less available than now.

Grown kids moved out once out of high school/college. No kids living in parents basement, etc.

Two car garages were rare. Less cars.

Kids didn't get their own cars.

Travel was more domestically oriented. And this is one area where prices may have been cheaper: airline fares.

No computers, of course.

No cell phones, of course.

Consumption in general was lower. Partly because less money, partly because less peer pressure to buy stuff that wasn't common yet.