I think I agree with your idea that TOs shouldn't just be considered byproducts and ignored but I think your analysis of the graph is wrong.

If TOs are inherently (not just byproducts of more aggressive offense) more likely to lead to losses, you'd expect to see more and more gray as you go up and to the left and more and more yellow as you go down and to the right. Instead, mostly what I see is that it gets more gray as you go up but not necessarily to the left. In other words I think the graph shows you win more when you score more and that number of turnovers has less of an impact. I think the graph shows TOs don't matter too much if you score a lot ie TOs might just be a byproduct. But it's hard to say with those outliers and not a super huge sample size