Wait, why is Elon Musk being used as example of someone who doesn't need vacations? We don't know what his personal life is like, in comparison to all we know about his professional life. There is no data.

Digging into his personal life is widely considered off limits. Reporting is not done on it. If I were, for example, to assert that Musk has had two divorces in 2.5 years and that this may in fact reflect that his personal life is a mess, I'd probably get voted down. And maybe that would be fair, because who knows, maybe in that scenario both he and his ex wives are happy to end the lifetime marriage vows early. My point isn't that Elon Musk's life is a mess, my point is we don't know, so we shouldn't be using him as evidence of not needing to "balance" work life, unless we're ready to have an in-depth conversation about what most people consider (rightly or wrongly) to be off limits private matters.