I can’t answer for the person you replied to but I can answer for myself.
I’ve been there, tried that. Lots of people say X or Y is a better single player game than WoW. I disagree.
Over my 16 year WoW career I have tried Skyrim, Oblivion, Mass Effect, Bioshock, Doom, Fallout, Baldurs Gate, Dragon Age, and every other single player and multiplayer MMO you can think of.
The fact of the matter, that WoW, even with all its flaws, is still a very, very good single player experience. One can only be the dragon king so many times in Skyrim but WoW is (in theory at least) always evolving and adding.
They really need an official single player end game path. Way too many people play WoW this way already for them to continue ignoring it.