First of all, that's not my opinion. I'm defending the other guy. Since he's getting his opinion denied under the untrue argument that his opinion is contradictory, when it is not. See the user names.
Second point, "not supporting trans athletes because they are a small group" is not at all what I said, but you are acting as if that were what I said. Let me repeat it again so you can see the difference: you don't need to support every policy that claims to support a small subset of a group in order to claim that you support that group.
Since it seems hard to understand let me say an example. There is country "chairland" where the chairpeople leave happily. Inside chairland there is a town called "tabletown". Person A says: "tabletown people should have free access to Netflix!" And person B says: "No, I love chairpeople, but tabletown is not entitled to free Netflix". Is the claim of people B contradictory? Can't a person support chairland but not support giving tabletown free Netflix?
And yes, everything in that original comment made by the other guy are opinions. "Trans women should compete in women leagues" is not a fact, doesn't matter how progressive you are, it is under every definition of the word: an opinion.
You are free to have any opinion you want, I don't believe in thought crimes. I don't know why you place such importance on "contrarian". Is someone that has an opinion different than yours a contrarian? Are contrarian opinions not valid? Therefore, are opinions different than yours not valid?