Explanation:
Jem's new theory for why Boo hasn't left his house in so long is because he doesn't want to deal with the people of Maycomb and how mean and judging they are.
I think this very likely could be true because when Boo does finally come out he seems like a very nice young man but also very very shy. Boo does not like to talk to the others and wants to go back home quickly.
Hope this helps!