It could happen the future isn’t always certain. By making the [Battering Ram] available in the Feudal Age it will give the player a chance to counter the Castle drop strategy if they cannot progress to the Castle Age as fast as their adversary.
I created a thread last year where I suggested that a new siege unit called the [Staff Slinger] could be added to the game and be available in the Feudal Age. This unit could serve as an additional siege option together with the [Battering Ram] for the player during the second age.