the thing is, duraludon was designed as an ace and a strong pokémon, sure, but it was also designed to be able to gigantamax in the role of the ace, and therefore was given the stat spread and one-stage line it was. were the gimmick not such a worry, duraludon and what is now archaludon could have been introduced together, and duraludon with a much lower BST since it could evolve into its true ace form anyway. i do agree it's an awkward situation gamefreak created but i think the generational gimmick curtailing design carries the blame here