If I'm not mistaken the situation is as it is because it was pushed to develop as such.
Battleships used to be exceptionally excellent, then they were overused.
Now they're slightly less than exceptionally excellent and their use has decreased.
Furthermore, I'm rather impressed with the ease two bombers apparently have downing a battleship. Given that a battleship's shield recharges the damage offered by a supernova in the amount of time it takes to fire a second shot, the amount of time required for two bombers to destroy a vessel of that size I always imagined the task would be somewhat daunting for any less than four bombers.
