As far as I can see it's quite obvious that at least one client is planning to add support for DCC 2 in the not too distant future, and that if it becomes a success, users are prone to switch to those clients, and other clients are prone to follow. So what hapens to the protocol is probably not something mIRC alone can regulate.
As for filesharing being the downfall of IRC, you'll have to explain further why you think that is. The Internet itself has a structure that facilitates filesharing, and it's quite natural that the overlaying protocols come to do the same thing. If IRC should become the subject of a controversy because of its filesharing facilities, how exactly would that hurt chat communities? I've yet to see users steer away from a technical implementation to avoid its filesharing capabilities.
