$3.7 million sounds like a lot of money, but he could have earned more than that over 7 years if he just took a mid-level job at a FAMANG company. EDIT: saw that the founder lives in Birmingham, Alabama. So yes, $3.7 million IS a lot of money.
Unless you're doing infrastructure stuff at Netflix, ad work at FB or Google, or some high level stuff at Microsoft you're not making half a million a year, and you're not doing it at a mid-level anything, anywhere.