Giorgio Armani didn't accomplish anything until his forties

Put it like this: I'd say that the average being 29 means that around 80% of founders funded by YC are below 40.

From https://hbr.org/2013/06/entrepreneurs-get-better-with/:

“The average age of a successful entrepreneur in high-growth industries such as computers, health care, and aerospace is 40. Twice as many successful entrepreneurs are over 50 as under 25. The vast majority — 75 percent — have more than six years of industry experience and half have more than 10 years when they create their startup,” says Duke University scholar Vivek Wadhwa, who studied 549 successful technology ventures. Meanwhile, data from the Kauffman Foundation indicates the highest rate of entrepreneurship in America has shifted to the 55-64 age group, with people over 55 almost twice as likely to found successful companies than those between 20 and 34.

The narrative of "it's hard to start a company when you have a family and a mortgage" might seem intuitive, but the data around entrepreneurship and small business ownership in this country shows that most people don't start successful businesses when they're young, single and have limited responsibilities.

> If you are an engineer, you likely graduated at 22. By the time you hit 29, you've had 7 years of real world engineering experience.

> Good enough to start your own company, in my opinion.

I don't want to discount the value of engineering experience, but this is hardly all that's required for success. One should not mistake Silicon Valley investors tripping over themselves to provide seed funding to engineers with the creation of successful businesses. A lot of the startups today aren't going anywhere, and you just don't hear a lot about the failures because employees typically aren't out of work for long when the money runs out.

Not necessarily. In my case I had far more financial independence at 40, no debt, and all the kids were out of the house for the first time in my life. Car fully paid off. In my 20s, I wasn't in the position to start a business because I had mouths to feed, at least not without external capital sources.

Yes, but they often have more support too. At 31, I've got a wife who can support the household, money in the bank to pay for capital expenditures, the ability to get a business line of credit, etc. If I quit my job to start a company, I wouldn't be staring down the end of a fixed runway. At 23, I would've been burning a fixed amount of cash needing to make things work before it ran out.

It's easy(ish) to find someone with entrepreneurial drive and technical skill. Far more important is the wisdom to know when to listen and when not to listen (and corollaries about hiring good people and managing). Those are critical for long term success and difficult to learn.

It's sad that there's a cult of youth in the valley because a lot of these skills develop over time.