If you come up with a way to accurately filter polite comments then you can either 1) make lots of money turning it into a product or 2) watch it go obsolete as

If you come up with a way to accurately filter polite comments then you can either 1) make lots of money turning it into a product or 2) watch it go obsolete as people modify their word choice and sentence structure to say equally awful things in different ways. That aside, it doesn't seem like stomping on anything to say "I want productive conversations only and it's my property so I decide what is productive" The idea that anyone should be able to say whatever they want on someone else's always seemed extremely entitled to me. The idea that no one should say anything except on their own site seems to be an extreme limitation on free expression.