I've for some time wondered how straightforward it would be to have a transponder automatically squawk something from the 7000 series when an RA is triggered.
This would mean the controller would lose positive identification of which aeroplane is which in the situation at a fairly critical time. Dumb idea.
In both the TCAS RA I have been involved in I was able to reassure the pilot there were no aircraft anywhere near him (that I knew of anyway). If there had been another I could have passed the traffic, which could help ensure a coordinated response, or I could have passed a reacting pilot traffic on a third aircraft his reaction has compromised separation with, or even arrange separation with that third aircraft.