The Dave Ramsey Foundation has done numerous studies and analysis of the middle/lower classes feeling the pinch. Yes, there is absolutely an issue with lack of rising salaries and rising costs of necessities, but the largest issue BY FAR is cultural and decision making.......by a large margin.....
For example,
Often people say things like the following, "In the 1950s a single middle income family could afford a house, etc, etc, etc. But now you can't do that.......Look at the prices of the house, cars, etc.........."
In the 1950s, the average male would graduate HS and immediately start working full time somewhere.....let's say a factory. So, from agea 18-23 they are making good money and getting a head start. Today often, a large portion of people aged 18-23 are not making good money but trying to fumble through college for a gen-ed degree that won't amount to much.
In the 1950s the average debt/bills/costs would be a mortgage, a single car payment, and utilities.....no credit cards and no personal/education debt. People didn't go out to eat much at all. Much of the groceries were canned and boxed goods as opposed to fresh/organic, lots of choices, etc. People drove an average of about 6,000-8,000 miles/year on the 1 family car. Now a days people feel the need to have 2-4 cars per household and drive 15,000-20,000 miles/year. There were no cell phone or internet bills. No costco, amazon, gym memberships. No TV/streaming bills. Houses were tiny.....and most didn't have AC at that time (AC wasn't widespread in houses until the 60's and beyond). Cars didn't have AC, tons of safety equipment, computers, complicated drivetrains, etc. People could do a lot of the maintenance on their houses/cars themselves. No $7 coffee or ice cream runs.
People were more likely to relocate for their jobs so that they could live. They didn't try to live in a high cost urban area on a poor budget. Kids didn't get new clothes every year....and often lived off hand-me-downs. The average number of clothing items in the average mother's closet was <10 items/dresses. Vacations were low budget and often were staycations. The parents of the people in the 1950s went through the Great Depression. As a result, the people of the 1950s were conditioned to save (money and junk) what they could whenever they could. On, and on, and on, and on.
The point being that 95% of all the expenses that I listed above are choices.....not necessities. And there are so many more that I didn't even list. These are all barriers to wealth. The wealth inequalities that we see today would still be there.....as they will always be there.......but it wouldn't nearly as pronounced as they are if better choices were made.