Seriously... you mean you only ever went to 2.0 maps one time? You didn't go back for hunts, new quests, seasonal events, Fates, relic quests/fates, etc?

Even if there's not a big reason to go back now (and there kind of is, with hunts and fates and such) there will be future quests in these areas (3.1, 3.2, etc). You're not done with them forever (unless you just quit or something, of course ).