Half the Diablo 3 team is ON the WoW team. That's how Legion was created.
Legion was the Diablofication of WoW. Insane RNG, infinite content in Mythic+, loot raining from the sky, meaningless loot, dumbed down class design etc etc etc
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Transmog was added to the game before D3 even came out.
The rest I agree with. The Diablofication of WoW was a cancer that still hasn't been cured.