My guess is that chins might be helpful for newborn suckling infants, perhaps helpful for feeling when the nipple is off-target when rooting. And why other mammals don't have chins - aren't our sticky-outy boobs quite unusual too?

3.33.

I have grievous doubts about that call-out article. Not that it doesn't apply in certain circumstance, and more often than not when it comes to online interactions, but for real-life and face-to-face people I tend to beware of people who do their shouting at other people in public, unless it's an option of final hope. Or, rather, 'never work for a boss who disciplines his employees in public' is a maxim I have discovered and have yet to find an exception to.