I think punishment can reduce honest opportunities when you go from zero jail to some jail, but once you're in prison for a year, my guess is the additional effect of having a record and disrupting your career is lower, with basic ways you'd expect like being out of contact with people you know, or being behind on technical training.

Likewise, I think networking also doesn't account for much when your prison sentence is five or ten years instead of three. There's a big jump from zero to one, and a much smaller jump after. (Regardless, that's one reason why I explicitly excluded organized crime.)

These are a few reasons why I think corporal punishment might be a good idea.