You Said It Beautifully. You Still Lost.
Speaking perfect English ≠ winning an argument. There are two skills hiding inside "good communication" — communication (can you say it clearly?) and articulation (can you make it land?). Sometimes the guy fumbling for words out-argues the guy who sounds like a BBC anchor. This post explains why, using pineapple pizza as evidence. Grab a coffee — actually no, this'll be over before it gets cold.