Perhaps i misunderstood the quantum of founders v coworkers etc - I assumed the latter would have been more frequent.d

Regardless, I do believe you aren't properly weighing the cost/benefit or risk/reward properly in public v private situations. One can have all the skills in the world, it isn't going to get the risk to zero. And if the reward is little, it doesn't add up for many folks.

I'm not a public person so I'm speculating.