In my view, instead of cutting down on your fun time and activities, you can cut down on your expanses, so that you need to work less and thus create more free

In my view, instead of cutting down on your fun time and activities, you can cut down on your expanses, so that you need to work less and thus create more free time for yourself. It's much healthier to work half-time or 3 days a week or something like that - and then use that extra time for your own projects and still have enough of it left for a normal life, family, friends, reading books, going out. What author proposes is certainly doable, but not something I'd really want to do to myself: no relationships, no tv (or books or games or sport), no much social life, just work and sleep. Maybe I'd do it for a while if I had a really promising, unicorn kind of idea, but just to fool around with side-projects and learn new stuff it seems like a hell of a sacrifice on his side.