IDK - the whole concept strikes me as being a manhood measuring contest.
The bomber killer wasn't the airframe but the missile - do you really need a Mach 3 interceptor carrying three or four Eagles / AIM-47/.AIM54 when you can have a larger number of AWACS and low cost Missileer style planes loitering to break up the bomber formations. With far more bang for your buck.
Well my understanding is that the 1960's era AWACS type air craft left a lot to be desired and in that era NORAD / ADCOM was heavily reliant on ground based radar systems.. I also suspect NORAD / ADCOM in that era also liked having interceptors that could likely get close enough to their targets to be able to employ an unguided rocket with a nuclear war head in case the bombers had effective ECM, Chaff etc that could counter a long range AAM.