I don’t believe this has ever been brought up as a point against RDF, but that’s fine. I’ll try to answer this as best as I can. Clears throat
Because by patch 3.3 (or in this case, 3.4) the world quests in Azeroth were nerfed to the point that most classes could solo them, pretty consistently, as long as you were on level or a couple of levels above. There are probably exceptions to this, I haven’t leveled Rogue, for example. This type of gameplay just does not exist in 3.3.5, with or without the RDF. There aren’t as many people questing through Azeroth to begin with, and the people who are either a) have heirlooms, so don’t need help, b) aren’t on their first character, so can probably afford decent leveling greens, or c) just doesn’t /need/ the help anyways.
I don’t believe this is a real argument against RDF, as this isn’t a problem caused by RDF. I am currently leveling a mage, wearing entirely BoE greens (and one or two cheap BoE blues I found on the AH) and have only once actually needed to group for any of the “really hard” elite quests. I don’t play Mage. I never did, never have, literally the first time I have played a Mage… and haven’t really needed to group much at all. Even for the Hinterlands Elite quests, frost mage gets to kind of walk through it if you plan your pulls even mildly intelligently.
There ARE valid reasons to not want RDF, this isn’t it.