Do you think Respec options lend some weight that they plan even more important content for Skyrim? It's kind of a weird feature to include this late, unless they plan on aiding you to "think your build ahead" for possible new quests in the future.
There will be more Dlc's and More quests Since Dragonborn sold or will sell Pretty well.
And they might have added that, Because the fans (Us) Demanded it.