All it takes to be a CEO is to be the person in charge of running a company. There are a lot of companies that are a lot of different sizes doing a lot of different things. If you start your own company you’re the CEO, but you’re also the head of sales and the person who makes coffee runs.
The stereotypical CEO (who makes boilerplate, sanitized public statements) is stereotypical in the first place because they run big companies, reporters care what they have to say. If you read the news you hear their words a lot.
Smaller firms, self started firms, and a lot of the more unique operations that would have CEOs that go against the stereotype don’t make the news often, so the stereotype stays intact.