Eh, it's a simplification. Legion, sure, but Cataclysm had less relevant outdoor content than either Wrath or TBC in its final patch by virtue of there not being a final end zone. I agree with @
Dioporco about ZM or Nazjatar not being the bees' knees, though I've had some fun with both, but purely by existing these zones offered more than 4.3. The TBC and to a much lesser extent Wrath rep grinds being actual content compared to Cataclysm's 'lol, put on a tabard and run dungeons' also made their worlds more relevant.