I've worked at startups that have had exits and the employees got zilch. I think even in the startups with exits the probability of an employee having their equity turn into cash money is very low (also I doubt 50% of startups have exits - I hear a number of 10% more often and even that seems high, I'd imagine 10% of YC startups have an exit and they are the most likely to succeed so I imagine when you add in all the other startups that percentage gets far far lower).
Skill issue
I thought this was sarcasm initially, but I think on looking at the rest of your comments that you are actually being serious. wow. Glad I've never had the pleasure of working with you.
But most startup people don’t work at most startups.