I think with the job finally being launched and have experienced how it is to play with it I can finally give a solid opinion about this topic..

I'll simply quote myself from another thread about BLU for matched content.

While BLU's tanking abilities can ruin any regular run of content if a player is clueless or malicious enough, the job itself doesn't break ARR content (RDM's ridiculous potencies break ARR content more than BLU can do it really) so I can't see why it is gutted from random matching on the Duty Finder, specially it all being 4-year old dungeons, raids and trials.