TOAA is more powerful than Pre R Beyonder ever was.
TOAA retconned him and made Pre R Beyonder Post R Beyonder, therefor less powerful than he was when Beyonder first appeared.
He made out of Pre R Beyonder whatever he chosed and that was making him Post R Beyonder, far less powerful.
At first Pre R Beyonder was the most powerful, but now many are more powerful than Beyonder, why, because TOAA decided that.
Only TOAA can return Beyonder to his previous state, to Pre R Beyonder.