Why does Apple bother with the 13 inch MacBook Pro if it has the exact same processing power as the MacBook Air? Touch bar and 2 extra hours of battery life are

Why does Apple bother with the 13 inch MacBook Pro if it has the exact same processing power as the MacBook Air? Touch bar and 2 extra hours of battery life aren't enough to differentiate the two. My guess is that Apple does intend to differentiate the M line but hasn't been able to do it yet, for what reason I don't know.