You know very little about photography. The pre-flash you are wanting would require way more power that the LED light could hope for on it's best day. You would need a flash bright enough to get everyone's pupils to constrict to avoid the red eye. Apple provide post processing to get rid of the red eye.
Both these points would have been so much more eloquent without the first sentence.LOL! Sad you are even thinking like this. It is all about physics here and large pupil openings will reflect light from the retina and there is little that Apple can do about it even if YOU demand they do something! LOL! They could move it to the other end of the phone and it would help little to none while imaging a group of people.