Claiming that words do not mean what they plainly do mean would be consistent with his other assertions that words do not carry the semantic content and cultural significance that everyone else understands them to have. He has claimed that using a racial slur against someone has done something bad is not a racist thing to do, apparently because it is directed at one specific individual rather than explicitly at all people in that group.
His last sentence makes explicit, I think, that he simply does not grasp that the meaning of language is not a matter of subjective opinion but an empirical objective question of cultural consensus.