Also, yes, hiring is difficult. Do you really think you are learning how to do it properly by working at Big Corp first?
Do the big companies you work for not have people interview with employees in their particular role? It seems relatively common among my friends for them to be interviewing people just 1-2 years younger than them, either for internships or to fill the position they're about to be promoted out of.
Some people are geniuses and can run billion dollar companies when they are 16. Other people can benefit from learning by doing for a few years. Everybody is different.
There was study that showed that entrepreneurial success has extremely weak correlations with previous experience.
Most successful entrepreneurs that I know were terrible at first and had little experience, but there companies still succeeded.
I know experienced people that started companies, and did things right and failed.
The difference was that things were in the right place at the right time.