sorting things by kudos is an algorithm, it's just a transparent one.

Yeah - it's a little scary that "algorithm" has come to mean, by synecdoche, "commercial algorithm that decides for you what you want to see based on a company's agenda." CS students all take classes in algorithms. The way you learned to multiply multi-digit numbers is an algorithm. It just means "a way of solving a problem that has a description so precise that a computer could use it."