The problem is by the time you've saved up $200k, most people are committed to a certain lifestyle based on their annual income. They're generally in their 30s or older, married, couple of cars, kids in school, mortgage, used to spending $X/yr on a vacation, etc etc. And, they've worked so hard to save up that $200k that it's unlikely they burn it to fund living expenses while they work on a startup.
Most entrepreneurs (generally, not just tech) are in fact in their 40s-50s. Well established professionals with good relationships and skills. Thing is they are usually doing it with Other People's Money, not their nest egg.