I played all of those games, and more, and I can say with considerable certainty that they "failed" (quotations because I have a feeling your metric for failure is pretty silly and wrong) on platforms of more than just economy. Wildstar for example had a great economy on its more populated servers, with CREDD cheap enough for the average player to earn, but pricey enough to be worth paying money for. It failed because of poor endgame execution, among other things. Guild Wars 2 (which I would frankly consider a success still, if not a blowout one) also suffered from that. Aion wasn't designed for the western audience it got released to and suffered, and Tera had very little going for it beyond a bunch of slut suits and good combat. To point at all these games and try to finger one facet of one facet of the entire gameplay experience as the culprit of failure is utterly laughable.