On one hand, his alalogy is a little more apt than he think sit is. On the surface, it's just a little harship, right? A few weeks recovering in the hospital, versus just not sleeping with men, or not dancing the night away with the girls, or a number of other seemingly trivial things. However, the psychological trauma of having a trusted loved one turning on said child has a far greater reach than a few weeks. Even if you spent the rest of your life explaining to the child that it was only done to get him a fortune, enough to last him the rest of his life, the child will never, ever be able to trust you fully again, always having to wonder waht else could bring out that brutality once more. Likewise, repressing any and all desires you may have, shunning men to force yourself either to women, or a life of celibacy, or shutting down your libido tend to have nasty psychological effects. Just look through here to see what happens when a sublimated sex drive is faced with even the slightest whiff of temptation.
However, where this falls flat, as is pointed out here, is that it's not like "Punch your kid, and he gets $50M." It's "punch your kid, and when he moves away from home, we cut off all contact between you and him, disallow him living in even the same country as you, and once he's far, far away, then we'll give him the $50M." You have no guarantee. You can't confirm the kid ever gets a dime. For all you know, you beat your child to hospitalization for nothing at all.