Because it often means that you're onto something. Polarized opinions are, by definition, extreme, and people that are really, really passionate about your project are often worth the cost of having the same number of people hate it.

Obviously there are limits to that idea- if people hate it because they find it offensive then you might be in trouble. But if they hate it because they think it's stupid (as here), they'll likely just dismiss it and ignore it.

He was being smart-alecky. He feels very strongly in one direction about a concept that means "divide or cause to divide into two sharply contrasting groups or sets of opinions or beliefs."