How is it "now worthless?" The power (and usefulness) did not decrease at all. There will just be something marginally better. You couldn't sell anything you got with Karma anyway, so don't give me BS about that price dropping.
There is one other point to make: Exotics are available as early as level 60. Ascended items are just 80 only (and a little more powerful). There won't be anything left for them to add (other than more Legendaries) The only reason whatsoever that "requires" Ascended armor is if you plan on constantly repeating Fractals, which I would imagine would get dull rather quickly. The difference between Ascended and Exotic is too small to make a difference in WvW: the better play will still win in a 1v1 fight, and a 1v zerg will always go in the zerg's favor..
Even so, I'm in zones everywhere, despite having 100% map completion. I like helping friends do things and sometimes I just want to leave Risen Putrifiers well behind (though I'm working toward a Legendary, so most of my time is spent in Cursed Shore to drum up the funds/skill points/materials)