Isn't this already adjustable through the AI's "Courage" value? i.e. higher values mean less sense of self-preservation in following orders.
Let's consider the alternative: right now it's most effective to focus fire on one bomber at a time, but the rest of the bombers in the wing continue their pursuit, so there's target prioritization and wingman management that needs to be done to defend effectively.
If this behaviour was altered, it would encourage players to spray bomber wings with laser fire to force them all to break off their target. They would still be easy pickings for an interceptor (can't win a dogfight), but this time they would have made even less progress towards their objectives. Right now this effect is a niche held by specific anti-bomber-wing weapons like the Flail/Morning Star and EMP missiles.
If AI tweaks in this direction are to be made, I'd suggest having it kick in for the last bomber in the wing when there's no point in drawing fire away from its wingmates. On the other hand, the sooner that last bomber dies, the sooner the next wave arrives. This suggests the tweak ought to be an AI profiles flag that can be used depending on the writers' preference for enemies as either cannon fodder, or equals in combat. Further, bomber pilots should be more courageous when they have defensive turrets allowing them to stay on target while also defending themselves.