Don't squadrons with BOMBER use their hits and crits to reduce shields? (without resolving the crit effect)
The rules say it's considered damage.
Yes.
With the Crit Icons Red dice have a total of 6 damage on them. This means an X-wing does, on average 6/8 = 0.75 damage against a capital ship.
Without the crit iconcs Black Dice have a total of 6 damage on them. This means an A-wing does, on average 6/8 = 0.75 damage against a capital ship.
The only advantage of an X wing has, is the ability to resolve critical effects.