Otherwise it's a hobby, and enjoying your hobby 10 hours a day, 7 days a week is an envious life, if you can afford it. (Barone specifically could not; he had to have a part-time job as an usher in a theater; that was work.)
It's only work if you tolerate it for the reward on the payday.
All of these can be hard work, All of these can be taxing, all of these can be intrinsically fun and rewarding.
I wish people would stop conflating work with just employment.
It is trivial to come up with activities that can consume a lot of time, but don't provide financial rewards.
Game dev is an arduous and draining process that both requires the patience to go through periods of dreary work where no progress seems to be made and yet the creative spirit to devise art, concepts, mechanics, rules, etc. If I had the time, I could easily see myself spending multiple years on a project like that without the need to see any financial reward. I wouldn't see it as work, I would see it as Work with a capital W. A hobby that requires a lot of personal effort but something I do because purely for the joy of doing it.