That's what most startups do. But, it's not clear if it's a net benefit because most startups also fail.
Another way of looking at it is finding a group of motivated 20 somethings is almost trivial. Find a motivated group with 20 years experience is vastly harder because it's a smaller group who have less interest in joining a startup.
PS: IMO, it would be a really interesting experiment, but I am not sure how you would go about it.
Finding motivated 20 somethings is even easier when they're motivated by the opportunity of working with someone like James Gosling. He convinced me to work at Sun when I was in my 20's, and that was years before Java.
I think you're looking at this wrong. It's not that a startup chooses between young/inexperienced/cheap vs old/experienced/expensive. It's that a startup doesn't get to choose because startup life is brutal. It basically requires you to have no family and kids, so only young single people are willing to do it.
Being 40+ does not prevent you from being single. Further, long hours and lack of skill are related. I am not saying you would always rather have say ~35 hours a week from John Carmack vs. 80 hour weeks from 2 or 3 awesome 22 year olds, but adding 22 year olds also scales poorly.
No, VCs have told you that "startup life" requires this, and you willingly believed them without question.
It is possible to start a company without turning the first 10 employees into desiccated husks. It's just not possible to do that while also doing what your VCs think is necessary. Maybe that's a thing to work on changing...
I don't think that demographic exists (really motivated people with 20 years experience). I remember Paul Graham saying something along the lines that he would never do the startup thing again even if he was dead sure it was a good idea because Viaweb took years off his life. Why would he go back and do it again? Why would anyone with a career and a family want to do that? It's hellish.
The problem isn't that that demographic doesn't exist. It's that you can't hire them on as employees.
Driven, talented, experienced engineers have been paid six figures for a decade and presumably have saved some of it. If they don't want to do the start-up grind, they don't have to. If they do want to do the start-up grind, they can do so as founders.
I still don't believe it's possible, at least not often. Hiring a senior rockstar/ninja/10x whatever means you have to offer them more money than they're currently making (which you have to imagine is a lot) and/or they need to really be so invested in your idea that they're willing to drop everything and join you.
I'm not saying this from a position of authority, I haven't founded a startup or anything like that. But the average age of a startup founder is mid-20s IIRC, and you'd have a hard time convincing an extremely talented individual, who's older than you, to sign on.
It's possible. I've had people older than me join me. I've got multiple startups under my belt.
The hardest part is not getting them to join you.. the problem is getting them to stick! Especially in the beginning at a bootstrapped startup without a salary. Simply put, they have other options -- a Real Job(tm) or career they can go back to; and those options start looking better and better when things are bumpy (esp at the beginning). But, you can compensate for that. (by aggressively compensating on actual profits.)
On that note...
If you're reading this thread and have lots of experience and looking to join a hot security startup, we're looking for both experienced and inexperienced rockstars/ninjas/10x/etc. Please email me at first.last at userify.com. We have specific needs in the areas of enterprise sales and marketing, as well as engineering, security, systems architecture, Go, Python, and we're also looking for a strong Windows lead.
Another way of looking at it is finding a group of motivated 20 somethings is almost trivial. Find a motivated group with 20 years experience is vastly harder because it's a smaller group who have less interest in joining a startup.
PS: IMO, it would be a really interesting experiment, but I am not sure how you would go about it.