It isn't because WoW is old because there are still several games that were released in the last 20 years that people play to this day. Baldur's Gate 2 is still revered as one of the greatest video games if not the best in History. Diablo 2 still has hundreds of thousands of subs and both games came out in the 90's. Lot's of people still play morrowind and oblivion as well since they were classic appealing video games. Plus lots of people play on private servers wow feenix has about a million subs so that should say that good video games = good subs. Common knowledge would say that world of warcraft has become a bad game over the years and only the fanatically loyal (myself included) remain.

I didn't find the right solution from the Internet.

References:
http://www.mmo-champion.com/threads/1422484-The-real-reason-wow-is-dying

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