I hear you, but Henry is not a person. He’s a character on a tv show and in the very last episode we saw our young Henry wearing fairytale clothes in the Enchanted Forest 2. We know that Henry wore fairytale clothes all the way up till he met Ella and the ten years after that with Lucy. It is odd and feels it off character for him to wear that. It is a bad creative choice by the people who make the show.
Incidentally, I also find it extremely out of character for Emma to wear a big flowing white dress. I really can’t believe we never got to see Emma wearing an outfit like Snow’s forest outfit on the show. Emma’s wedding outfit was horrendously out of character.
Henry’s outfit is not that big of a deal, but I think that character has made the choice to live in the Enchanted Forest and an outfit in keeping with that choice would make sense.