Well, I wouldn't take Protestant theology at face value. It's a rationalization of modernity, and of the turn towards secularism, towards the shifting of social power from the Church to the institutions of science, capitalism, democracy, and the like. Protestant individualism is a Christian recasting of the ancient Greco-Roman themes that found their way, via Gnostic heresies, into the modern age. "Prevention" of idleness" as an exercise in "spiritual stewardship" is only a Christian excuse for the fact that we must keep saving ourselves because Jesus never returned to earth to usher in God's kingdom.

I wouldn't say that labour on the whole is a reformative punishment in Christian terms. The theology changes with the real-world circumstances of history. The sense that civilized work is a punishment made sense in the ancient world when the transition between primitive and civilized societies was fresher, and when the conditions of work were harsher because the level of technology was lower. Then Christianity had to adapt to the conditions of modern progress, and it did so with theological rationalizations. That's how I'd interpret it anyway.