While 1-7 is a pretty clever tongue in cheek perspective, it's not at all what Max Martin does. Arguably he's the king of modern Pop music hits - I mean, he's orders of magnitude more successful than second place. It's rare to find interviews with him but he does drop some hints at his methods and approach (balanced lines, extreme vocal comping detail work) which takes a lot of the mystery out of it.

Basically though #6 explains how acts like Cardi B can chart, because Pop music is a commodity, it's not art. Something like Gotye's hit definitely falls into #7 in that regard. "What's good isn't always popular, and what's popular isn't always good."