Tony's right, he has no idea what he's talking about, but that doesn't stop him from dragging him over to the tree. Tony can't see it, but he should be able to smell it. It's not the right kind and it doesn't smell like pine, but he takes Tony's hand so he can touch the leaves, feel some of the ornaments. He know Tony has a vast imagination and can picture it in his head, if he wants. This would be much more difficult if he were Thor.