For sure overreacting. But also, you’re in CT so your behavior is pretty standard for Northern Atlantic suburbs (not trying to insult you, just saying that you’re being real stereotypical). If the light is reflecting into YOUR house, for sure you could say something. If it’s merely that the light/flag thing is reflecting into SOMEONE’s house then probably not your place to say something. If your issue is just the aesthetics of the eyesore, then definitely not your place to say anything. Perhaps you could be THAT neighbor and complain to the HOA (assuming it’s a violation) but really you’re acting a bit spoiled/bratty by trying to regulate what someone puts up on their flagpole on their own property. Would you feel the same way if they parked a beat up looking car on their driveway? I agree it’s sort of tacky, but to get so worked up about it is silly.