I noticed a lot of the artists get ‘Joseph’ fairly correct, in that he was probably waaay older than Mary. Perhaps in his 30’s though. Mary would have been in her mid teens.
Tradition at that time was that a man could not marry until he had a good stable income usually a skill or trade, which he would have been apprenticed as a teenager. Joseph was a Carpenter and would have been considered ‘middle class’ for his time.
Mary was ‘betrothed’ to Joseph through familial obligations from the time of her birth and would not have had any choice in the matter. Happens still in the Middle East and parts of Europe.
This would account for why Joseph essentially disappears from scripture after Jesus in the Temple as a adolescent. And why Jesus, on the cross, asked John to take care of his mother, fulfilling one of the 10 Commandments.....................
A system like that would generate a surfeit of middle-aged widows.
Seems like a graduated apprentice could become successful sooner than you suggest—early twenties, perhaps.