Honestly that is not what he is saying.
His argument is that the Dungeon might seem hard or unfair because they are not designed around the idea of a holy trinity.
Thusly the wow/everquest players will have a harder time.
Us who are use to action packed boss fights in other RpG's where you dont necessarily have a tank find it easier to adapt.
Getting your behind handed to you again and again is not fun for all.
The Yanger should remember how the Cataclysm heroics where received. Most of us "old" players welcomed the change. However the vast majority of players where not ready to having to learn to play their class and use CC etc in order to beat the content.
They wanted the reward without the risk.
So Blizzard nerfed the heck out of the heroics. Loosing the players that wanted a challenge but pleasing the majority of wow players. Which in all honesty are casual gamers nowadays.
GW2 is a harder game because it forces you to be more active in battles. This goes for dungeons but also for leveling.
This is a design choise. Its not worse then wow nor is it better. That is simply a matter of taste.
The majority of wow players will not like this change.
Gamers who dont enjoy the stale playstyle of WoW or Tor will however most likely enjoy GW2.
While I agree, there are moments of insane WTF bullshit in the dungeons that are just inexcusable. For example yesterday I ran CM explorable butler path with some Gaffers, and the cave with OP rangers at the end and a spike trap was tedious as hell.