I have a case on it anyway so meh, it’s one of those things. I have had so many iPhones I have had to exchange to Apple in the past for more worse defects than this so as you say I may as well keep this one instead of getting an exchange which may even have an even worse defect.Sorry but can't see it.
I think you are making the right choice about contacting Apple. No way if my phone was perfect except for this that I would take the risk of exchanging . . .. not worth it!