The hierarchy of wage looks something like:
1. hourly pay (how many hours you can work sets the maximum possible salary)
2. base pay + cash bonus (the cash bonus starts to increase your earning potential. Sometimes the bonus can be huge, for traders, salespeople, etc.)
3. base pay + stock options (the stock options can outsize your base pay by big margins)
4. stock ownership (almost all your wealth is tied up to the stocks)
The vast, vast majority of people are stuck at (1), and will never move to (2). Nearly all billionaires are at (4).
The average worker will work around 100k hours in their lifetime. If you started working today, with a 2% inflation rate, you'd have to start getting paid close to $6000 / hour in order to reach a billion dollars (pre-tax) in total income by the time you retire 50 years from now.
Another factor to consider, is that salaried workers can't use leverage to increase their earnings. A startup founder can find investors and raise money, which works as rocket-fuel for their company. You can practically outspend your competition. That is simply not possible for regular workers, without breaking rules (as in outsourcing your job, taking on several jobs and outsourcing those, while collecting).