When people talk about "The Algorithm", they're not talking about just some function that sorts stuff by X or Y, but an feed optimized for "evil X", usually trying to drive longer attention, or push up engagement.

If GitHub started using the submissions GitStars to recommend repos in people's GitHub feed, I don't think people would get their pitchforks out about "The Algorithm" in that case. But if GitHub started to make the feed so you spend as much time there as possible, by whatever means and potentially irrelevant stuff, then the GitHub feed would start being considered as one of "The Algorithms" by many, would be my guess.