By todays standards anything from back in the day is a zerg. People run out of things to blame so they choose to blame "zergs".
I actually hope that enough old players come back to form a big org, nothing better than raiding harpers back in 2016.
If you want anything to blame then its the complexity and unfairness that new players face. When i first played we stood a fair chance even against end game players, I even remember winning a raid where we got bombed as sweaters. These days? Its a joke.