The reason our parents could afford a house on a working class wage and we cannot is simply that we earn less than they did. Yes, I'm not kidding here, in buying power we're worse off than our parents were. Well, most of us at least. A select few are actually better off. Then again, it's that select few that probably don't even notice it.
I won't argue that the current generation doesn't earn less than the previous, but there is a bit more to housing than that. Housing coasts have gone up relatively also and there are multiple reasons for that. First, houses are bigger with more features than earlier generations, especially if talking my grandparents or farther back (50's or earlier). "Middle class" housing from that time period not only would not be acceptable to the average family these days, but probably wouldn't even but up to code. You had families of four or five in two bedroom houses the square footage of some living rooms I've seen. Go back to the 40's or earlier and you had shotgun shacks the like that were considered "middle class" back then. All that housing has been torn down and replaced with larger versions stuffed with appliances (which allows for less time homemaking that allows a two paycheck family). Then that housing that is in places that have jobs are getting so expensive because so many people want them, while housing in rural areas is not growing in worth because people aren't moving there because there are less jobs and living situations. The old industry could deal with small pools of slightly skilled workers producing simple products, while the current economy is seemingly demanding large pools of highly skilled workers capable of producing expensive products.
If I wanted to move back to where I grew up, I could just write a check for a house in my old hometown. I might even find a job, but it would require the one or two employers in the area needing my skill set, and few options except waiting for a spot to open up for me.