Just two things regarding the argument:
- Games in which the player has to read losts of texts and have long conversations with npcs are tend to be singleplayer games, not multiplayer games, since its a singleplayer interaction, with no other humans involved.
- Without your desired quest rewriting, a quest helper doesnt cause a linearization, just because players know where quest objective are. Players have it easier to plan their questing route, but thats all.
Good luck trying to make the devs change the way of designing quests(texts) though. Quest design has always been done very similar and since the Blizzard team cant even reinvent a working wheel, how could they design something new that turns out to be good?