I interviewed Jason about his book last year. Afterwards we spoke for an hour, and I’ve never felt better about my piddling career as an author.
Jason brought up lots of famous authors: Herman Melville, Cormac McCarthy, Tolkien. Melville basically got to take a year off from his magnum opus, then went back to being a clerk. McCarthy was a full time author for years—but only because he was so poor he didn’t have running water. Tolkien didn’t make money off writing until twenty years after LOTR when already primed to retire. Stephen King etc are (in terms of success, not talent) the fractional lottery winners of the literary world. Most of us are lucky to get paid at all. Academic books average around 500 sales in total!
I’ll add that Jason Parton and Andy Weir are two people I’ve interviewed that, when I quit the call, I thought “What a great guy! I’m glad success found him.” Very talented duded who are also just really nice human beings.