A recent blog post from the Kauffman Foundation puts it succinctly, when it tries to dispel the myth of the twenty-something tech wizard as the prototypical entrepreneur.
Citing research, they write:
In reality, the highest rate of entrepreneurial activity belongs to the 55- to 64-year-old age group over the past decade. And most high-tech founders are well educated and married with children.
Dispelling the Myth – Entrepreneurship.org.
This is in stark contrast to the meme that the young, college dropout is the model for the modern day successful entrepreneur.