NFL’s ten highest-graded wide receivers against man coverage

I'm confused by what you mean when you say this stat is arbitrary. They took every route each WR ran against man coverage and gave the win rate a number. That isn't arbitrary in the slightest. It doesn't show the whole picture at all, if that's what you mean, but it's an important statistic that shows a WRs ability to get open and make plays against a single defender. I don't think anyone is claiming St. Brown is the best receiver in the NFL but this metric is very telling for pure athleticism and talent as well as target opportunity. Obviously the guys most targeted in man coverage are probably the most trusted and/or most targeted by the QB on that team. And it's entirely possible that truly elite guys like Justin Jefferson, Chase, Brown, and Hill don't actually see single coverage near as much as someone like St. Brown. It's all just pieces of a larger picture.