Let's assume we have two people, and for sake of discussion, both will only work 8 hours a day. Do you think enthusiasm will trump experience and profissionalism?
I don't follow the latest trends in frameworks/languages, I like solid solutions over start up mentality of ship fast and think over the problems and design good solutions for my clients. I work with SV startups that have all these people that 'care' but I'm still called to clean up their shit. And because of this, I make very very good money. I still won't work more than 8 hours a day, and except for a couple hours to unwind (HN, news, reddit) I don't even touch the computer and spend the time with my family/community. And I can tell you, if sweeping streets paid me more, I would be sweeping streets. I don't give a fuck about the work I do. Want me to work on oil platform, if you pay me, sure! A social network for gerbils, if you pay me, sure! HFT, if you pay me, sure!