No is arguing that pitchers don't contribute to wins and losses (I don't think anyone is saying that). We are saying that the W-L stat tells you nothing useful at all about how a pitcher pitched. So, if a pitcher pitches 5 innings, gives up 5 runs, but his team scored 6, he gets a W. What does the W tell you? Nothing. If a pitcher comes in, gives up 2 runs and blows a lead, but then his team comes back and wins, he can get the W. What does the W tell you? Nothing. If a pitcher goes 9 innings, and gives up1 run, but his team does not score, he gets an L. What does that L tell you? Nothing. Yes, 100%, a pitcher contributes to winning and losing, but there are literally dozens of stats that tell you how he did that, and none of them are W-L. None of them.