As explained, ADS-B transmissions need not originate with the aircraft that is identified. If there is primary radar coverage an ADS-B transmission can be originated by ATC to represent the majority of factors that apply - location, speed, altitude, heading are enough to provide useful situational awareness. If they know any other information that also can be included.
I can’t see how this would work to be of any real value..
In remote areas using ADSB in, I can see all other aircraft with ADSB out. What you’re suggesting would cover only a small part of the airspace.
If all aircraft are equipped with out as a minimum, safety outcomes will result.