Did No Second Prances retcon the ending of Magic Duel?
Probably not, but I really can’t see any real animosity between Twilight and Trixie after rewatching Magic Duel’s ending.
The fact that it’s over Starlight makes it seem even more superficial. Celestia also curiously is oddly uncaring in that episode, because if she did care, we’d have no “funnays” with Twilight and there would possibly also be no conflict at all..