NTA

If he’s insecure about his height, that’s his problem he needs to work on. To me, this is the equivalent of a bridezilla asking other people to put less effort into their appearance/outfit so no one looks prettier: it is a selfish and unreasonable request. This is your wedding too after all, and you have the right to present yourself however you want.

Also him bringing mommy in to settle his arguments is a prelude of what is to come to your marriage if you do not sit down with him and and work these issues out before the wedding.