I'm in the same demographic (less successful than Noel, but I have made my living from game dev for the last 15 years, a lot if from my own indie games). I've used multiple engines throughout that time as they seem to have a lifespan before either tech or business reasons obsolete them (e.g. my first commercial release was made with Flash).

My only regret were the times I tried to roll my own, I would have saved a lot of time and effort focusing on picking the best tool for the job that saved me as much work as possible.

At the end I want to make games and not engines, and only do as much programming as I have to. All those person-millennia spent at epic/unity/etc actually spent doing a lot of stuff (even if you don't need 90% of it, 10% 1000s of people working for decades is still a lot).