Jesus came to fulfill the Plan of Salvation, that was his God given purpose and all that was important. Scripture says that his earthly appearance was nothing exceptional. All Mary needed was to be in the line of David, so once again, anything she had that was noteworthy was from God in the first place
I'm not saying "right" or "wrong". But it occurs to me that humans are social animals. "It is not good for the man to be alone." Every child is 'formed' by his parents, even if the formation is nothing better than challenges that the maturing adult must overcome.
So, and this is just a speculation, IF we assert that Jesus was truly human, AD IF we assert that humans are in some respect "formed" by their parents and home, THEN it seems the characters and graces of Mary and Joseph would have to be influential in the development of Him who was truly God AND truly man.