He's not concerned about looking weird. For certain audiences this is a disadvantage. But he is concerned about tying his computing down to his core philosophy. He did it so well that you can almost hear him when he's not in the room. We should all be such effective weirdos.
At some level we have to trust a substrate of computing to get anything done. Stallman's work to make that substrate as trustworthy as possible was very farsighted.