I find it only pretty strange that all dragonborn in MTG have tails and all dragonborn in D&D have not.Huh, they have removed it. To be honest, I don't think I didn't realise they didn't have tails until reading some sort of debate. I often use art from the internet to get some idea of what people look like, and those images (being independent artwork) often show them with tails. I must never have looked too hard at the official artwork.
And there are too many MTG pictures so that it can be blamed on a freelancer getting the description wrong (and no one got it right). It really looks like WotC wanted the MTG art to have tails but for some reason doesn't want them in D&D art.
Why?