I have worked for many startups and I can say for a fact founders below 30 in leadership are useless and will make a mess of things, especially when they dont have any prior experience. In contrast when the leadership is more than 30 and have prior experience they make decisions which are sound in multiple dimensions, both in terms of people, fiscally, in terms of technical capabilities and so on.

I have vowed to never work in a company where the CEO/directors are less than 30.