But on the other hand, you could be spending that extra time reading and learning about things for your own interest or socializing with your friends for your personal benefit and social health.

Ultimately there is a trade-off between spending time at work and for yourself/friends/family. What the OP and other recent posts are increasingly showing is that the amount of time we really need to spend at work (perhaps especially if you are a knowledge worker) is not as much as our normal hours dictate.

Culture is a strong force.