How many MMOs do you think have been released in western markets in the last year, exactly?
That's part of the point. It's been a long while since an MMO HAD to go F2P, and most that launch lately are already so. The genre as a whole was in a transition stage, clearly niche and/or bitesize gameplay MMOs going F2P or B2P (one time purchase) and then monetize inside for better revenue streams.
On the Secret World, they've been B2P for the longest time and Legends is a revamp to the game that will make it more action-like, which should bring more fans into the game. It's a brilliant story by Ragnar Tornquist that should be seen by more people.
MMOs are becoming less popular, but are still vastly successful. MTG is better served by either a big budget AAA singleplayer RPG which won't generate revenue outside of initial purchase price except DLC, or an MMO that can cater to an audience wanting to interact with each other and can have multitudes of microtransaction cosmetics that would give a steady stream of money.
Plus Cryptic already have a relationship with WotC, the CEO loves Magic, etc. There's room for it.