You are making big assumptions there. You don’t know what is in someone else’s mind.
On the rare occasions that I have been dressed up and somebody said, “You’re so dressed up” or something similar to me (and it does happen because people don’t expect it from me) I just take it as a compliment and say thanks and move on. I might give a little context for why I was dressed up if I felt like it (going to the opera after this, got an interview later, going to a wedding/funeral, just got this new dress and couldn’t wait to wear it, I love to get dressed up for the holidays.) I certainly don’t try to make the other person feel bad.