In 1968,for example,a new teacher's salary in the N.Y.C. area was about $5,000,or a bit more.Today,it is around $39,000; which is about 8 times more.Now,compare the prices of the same things,then and now and you'll see that there is no loss in buying power.
And if you want to talk about housing, comparing co-ops in Chicago with the same one's cost in the mid '20s,to today's price (and I am talking about the same apartment !),some are actually a bit cheaper today...including many updates.
Did you say mid-20s in regards to co-op prices? The mid-20s weren't a terribly healthy period as we now know. It was the lead up to the Crash.