This is fair in theory, and I imagine that some smart, high-agency people take advantage of the situation, but as is often the case, “down time" leads to more down time rather than more time to devote to career advancement, networking, and so on.
In fact, one might think that one day, when free of obligations and with plenty of gas in the tank that is currently used for work, one will pick up the barbell, take long bike rides, and build the body one has always dreamed of showing to their partner. But they are much more likely, instead, to spend more time watching the latest horrible Netflix TV series or eating burritos. The right analogy for mental and physical energy is not the tank, but the flywheel.
In fact, one might think that one day, when free of obligations and with plenty of gas in the tank that is currently used for work, one will pick up the barbell, take long bike rides, and build the body one has always dreamed of showing to their partner. But they are much more likely, instead, to spend more time watching the latest horrible Netflix TV series or eating burritos. The right analogy for mental and physical energy is not the tank, but the flywheel.