raise your hand if you will never not be salty about the lack of development of a friendship between Steve Rogers and Tony Stark in the MCU
If you're talking about the "vanity issues" joke from the special, I don't think Moffat meant Ten all the way through. If you remember the episode when Ten regenerated back into himself, then you'll remember that he actually said (when asked why he looked the same, and I quote) "You see? Used the regeneration energy to heal myself, but as soon as that was done I didn't need to change. I didn't want to. Why would I? Look at me!" So I think the vanity comment made sense.