It bothers me as well, and let me explain something:
There's a difference between a light in a game being bright, and a sudden, random flickering against a very dark background. I suffer from chronic migraines, and they can happen from certain events, such as me being dehydrated, needing something to eat, or sudden bright lights (especially in an otherwise dark area).
While you may tell people to "suck it up", what was originally posted was not something that is being commanded to be done, but rather, a suggestion. The flickering being moved to a different area, or removed altogether, would not hinder your gameplay at all, but would merely improve it for others. Sadly, "sucking it up" would do no good to the headaches I receive from such events. If it did, I'd totally do a lot more things that are otherwise restricting. It's less about the "flashiness", really, and more about the intensity of the brightness against such a dark background, and having it constantly go as you're concentrating on enemies for a good 20+ minutes.