I fail to see the contradiction.
My thesis is that McCree is fun not because there is something about McCree’s kit that makes him intrinsically fun, but because he is powerful, and people find powerful heroes fun to play. None of that is contradicted by anything I said previously, or the Mercy situation,
Then we look at tracer, also low pick rate and low winrate, but-
I’m gonna stop you right there actually. Tracer does not have a low pickrate, especially compared to Sombra.
For the last 6 months, Tracer has hovered around the 2% mark, and as I have argued previously (📊 The more things change: Crunching the numbers on the "impact" of the Sym 3.0 rework) I would contend that 2% is a fair benchmark for a balanced hero’s pickrate.
If anything, by the above method, I would currently rate Tracer as medium reward, high risk.
Sombra, on the other hand, is borderline trash tier, and has been for the last 6 months at least. So she woudl be accurately described as low reward, high risk.