Note that there is just a consensus that a supermassive blackhole is at the center of galaxies --it's a "maybe, presumed, likely", as it is with just any other

Note that there is just a consensus that a supermassive blackhole is at the center of galaxies --it's a "maybe, presumed, likely", as it is with just any other black hole. If you check the wikipedia page you link, it says: > A blazar is a very compact quasar (quasi-stellar radio source) associated with a presumed supermassive black hole at the center of an active, giant elliptical galaxy All we can say with confidence is that there is something massive and dense --doesn't mean the only explanation is a black hole.