Wow has its own style for graphics, the old world was updated with cataclysm, blizzard doesnt do mobile games if you exclude the port of hearthstone, they arent covering anything up by lying about their developement team. infact they are open about most of the changes to wow, yet people take it as conspiracy and lies because of reasons.
Overwatch isnt finished, its not even hit public testing so probably not a cashcow as its not even being sold yet.... Warlords has given room for everyone to get properly started before the next chain of quests, raids, events and features which hits with 6.2. Mists and cata did it aswell, i dont see what the issue is with smaller patches between raid tiers. We got to play highmaul out before we entered the foundry, and we will get to play that out before we hit Tanaan jungle in 6.2. (the story present in the live game even tells it flat out, Grommash is in Tanaan jungle and the iron horde is.... do the quests :P
Take a break if the suspense of whats next is unbearing
Blizzard does more things and do them faster cause their community whines and feel entitled like spoiled babies at times :P They sure as day arent lying.