Dungeons are literally the lowest form of social interaction in WoW. Dungeons require very little if any communication to kill bosses. Most people in dungeons are looking for a quick in and out.
The fact it teleports you into the instance is such a small issue with the existence of flying and summoning. The proposed LFG tool doesn't fix any of the issues that RDF solves nor does it help foster "social interactions".
These are none issues in Wrath Classic, RDF on it's own is a fantastic tool that solves a major issue with older and irrelevant content.