In reality "the pursuit of happiness" could mean working in a soup kitchen, meditating full-time, moving into the rain forest and living with a primitive tribe, or buying a farm and working towards becoming self-sufficient.
(Does this sound hypothetical? I know people who did some of these things, and some of them reported their happiness increased significantly.)
In reality it always seems to mean the narrow and small-mindedly unimaginative pursuit of money, power, and social status for the purposes of physical comfort, childish short-term ego gratification, self-importance, and conspicuous wealth/status display.
Sometimes a rare individual will produce something worthwhile as a side-effect. But don't confuse cause and effect - plenty of individuals chase these goals and produce absolutely nothing of value at all.
So there is no deep insight there. It's just a transparent exhortation to work, spend, manipulate, and consume in a very public way, instead of doing something more challenging with your life.
(From Wikipedia)