For founders, the question loses some of its meaning, because the company itself is intrinsically tied to personal goals. Founders tend to not refer to the company as "a job". It's something of a different beast. This doesn't mean that some time doing non-company stuff won't ever be required to maintain sanity, but the dynamics are pretty different.
For employees, which this post seems to be about, you're ultimately working to fulfill someone else's personal goals. There it makes a lot more sense to balance working on your own personal goals and pastimes or whatever with working on the goals of the person who's signing your paychecks. The problem is that if there's a sufficient supply of employees who are willing to forgo that for whatever reason (loving the work, not having much of a life, peer pressure) then they're more likely to be favored by the employers with the implications that go along with that.