> some authors have had good luck with self-publishing

Indeed. What are the relative statistics on authors who have managed to bootstrap themselves vs. authors who make a comfortable living through the Big Five?

It’s not common, but it does happen. Andy Weir, author of “The Martian” and “Project Hail Mary”, originally gave his work away for free online on his website. He only self-published to Kindle (for the lowest possible price setting, 99 cents) because some of his fans didn’t know how or didn’t want to manually install his home-rolled ePubs on their devices, and begged him for the Amazon/Kindle distribution.