90% of mounts have been recolors since the beginning. The stone drakes of Cata; the drakes and proto drakes of Wrath; the talbuks, wind riders, netherwings, and nether rays of TBC; and the racial mounts of vanilla. The only difference is these were given at sets from the beginning. Whereas more recently they've been making recolors of older mounts which didn't used to have recolors, which is where people's kneejerk reaction comes from. 6 recolors of the same mount for getting exalted = fine. Adding a recolor of an older mount for a content completely unrelated to the older mount's = lazy recolor to some people.
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Um, have you looked in the appearances tab? Every gear set going back to ToT had 4 recolors, with the mythic one having some extra ornamentation. Before that you had 3 going back to DS, and 2 going back to Wrath.