I get what you were saying and what the other commenter was saying. You’re saying that no knowledge is inherent, all knowledge needs to be learned.

The other commenter was conflating common sense with common knowledge, being knowledge that the majority of people know and can recall (but would still need to be learned at some point from somewhere).

I don’t think you are wrong, and I think the other commenter was trying to say that common knowledge changed over time (true). I hope neither of you let it affect your day too badly.