I don't see the way of your thoughts between quazar description (which is correct, quazar suck huge amounts of matter, radiating huge amount of energy. Some of the matter is ejected back as from sling (like that jet you can see, which will turn around and start revolving around that SMBH) and doesn't enter event horizon, you get turbulent gases - voila, galaxy) and conclusion, that black holes revert to a normal matter after some time.