I have yet to meet a single startup billionaire but i already know at least one person who made 1B+ through scripting and several who are in 9 digit range. It's just easier there because there is no law to abide (you are anonymous by definition, and frequently a sybil of thousands if not hundreds of thousands of fake people), and no need to "sell" or be liked by anyone.
It didn't exist before ~2017 because crypto/smart contracts were not a thing yet. SEO/SEO scams existed yes, but these never brought in comparable amounts of money and traditional startups looked more attractive in comparison. Today, many people just run dozens of solana nodes, guess how much they make?