The only issue I have with the old content is that not many want to do the old stuff anymore. I remember back when 2.4 dropped, everyone ran crystal and Syrcus tower like crazy just to level up. It became annoying after a while and tedious to level up, simply because I was under geared, and I was ilevel 90. Now that the new gear can be bought for nothing, the old stuff is skipped and the quests are never done. I'm a casual/completionist and I wish the old content would have been brought back. The hunts being done at low level really made things that much easier to level up. I remember how hard it was to get gear, now it's a joke and those that want to do the old stuff are stuck in the waits.
Why do them, you may ask, because it was fun to work as a team and fight the hardest bosses, beating them and getting the loot. To at least say hey we did it.