I'm not seeing why this is a hard concept.That is a contradiction.
A hypothetical ATG bowler struck at 50 against bats of average quality (who typically survived 80 balls) during their actual career.
A hypothetical ATG bat typically survived 100 balls against bowlers of average quality (who typically struck at 60) during their actual career.
This ATG bowler strikes at 60 against an ATG team. The bat survives 90 balls. Insert whatever numbers here. Both their numbers get worse against better opposition, like their averages would.