>No, you shouldn't have to work a 40+ hour week and then go home and practice to make a living as a software engineer. But if we want highly performant programmers, we should figure out the best ways to practice (and probably spend less--but more effective--time on production code to balance it all out).
You're coming very close to identifying a major problem with our industry that isn't likely to go away. Yes you absolutely do have to "go home and study" to keep up as a software engineer/programmer. This is due to two reasons:
1. Advancements in technology outpace us
2. We're generally overloaded by management that doesn't understand what we do.
As for #1 there isn't much we can do to change that, and who would want to?
But for #2 it's a major problem. In many cases our 40+ hours have to be filled with coding because of the unrealistic deadlines that are posed on us from managers who don't understand the work.
Most of us are managed by people who have no idea what we do. They want "more more more" in terms of features and gizmos but haven't the slightest understanding of what goes into it. Add in scope creep and wasted time with meetings (that make them look busy) and that adds up to a long work week for a developer. And when you ask for time to study or learn something new, the response is "sure, when things aren't so busy".
This just reinforces my belief that you need passion to do this. You have to love development so much you're willing to put up this stuff, work your ass off and still want to go home and learn more.