I don't disagree, we're not talking about absolutes here. But it's reasonable to consider that, all other things being equal, someone who loves their job may be less inclined to take as many vacation days compared to someone who hates their job.
Advocating for longer vacations, leisure time, and simply being disconnected so folks can develop their interests outside of work are important. However, most people spend most of their non-sleeping life at work. Accordingly, making work itself more fulfilling can often have a far greater impact than simply requiring less of it.