Our work-ethic as a nation seems to have declined. People don't really want to work hard anymore.
You looked at this graph and determined that's what the problem is?
How "hard" someone works and how productive they are are different things. The first is arguably subjective. Ask anyone if they "work hard" and they'll tell you they do, whether they work in a coalmine for 9 hours a day or sit in a toll booth collecting change or sit at a terminal in a Goldman Sachs office.
If I'm Bill Clinton, I can get paid $10,000+ to speak to a roomful of businessmen for less than half an hour. I could speak to them about anything - any number of anecdotes of things I've done and people I've met over the course of my life. The actual effort involved in that probably is not taxing for him. He's not spending hours preparing for the speech. He just has to show up, maybe look over a few cards an aide prepared, and be Bill.
If I'm a McDonald's employee, I can spend an hour walking around a kitchen, making fries, burgers, milkshakes and a number of other food items, dealing with customers, accepting payments, and get paid $8 for that hour of work.
Bill made $10,000 in 25 minutes. The McDonald's worker made $8 in 60 minutes.
Which one is more productive? Bill, obviously. But which one "worked harder" for the amount in question?
