Disagreeing with an idea you’ve never personally held is less influential than opposing one you have. If you tell me I’m wrong simply because you’re right and you have always been right, I’m less inclined to believe you than if you tell me I’m wrong because you used to think like me but have been persuaded to change your mind.
For one thing, if you fashion yourself to be the holder of all the true ideas, they aren’t your ideas. You got them somewhere. Tell us where. Own their borrowed-ness.
Don’t tell us a story of your correctness. Tell us the story of your conversion.