I'm still asking myself to this very day what was the hidden message or moral Kishimoto was trying to bring to the readers with this story? Anyone?
Easy, work towards the good of society. The thing is this is done in a very traditionalist Japanese way. Endure the problems society has while supporting that same society.
Though really, this attitude is very problematic for the Japanese. Despite having laws protecting people against sexual harassment, this mentality made it so women wouldn't report their harassers because it would make the company look bad. Kids who are bullied are expected to conform to the group, and people only really go after the bullies when it gets out (in one case, the families of the bullies ended up paying to relocate the victims family). Or we get incidents where foreigners are attacked by Japanese natives, and what do the police do? Say "Are you sure they are Japanese?"
Japanese values result in them sweeping a lot of things under the rug while children are expected to follow the example of their elders. Even when the youth see the failings of the older generations, they're expected to bow their heads, respect their ways and follow them without question. Naruto embraced this mentality as they transitioned him from an escapist character to the father of an escapist character, and since they don't want to make Naruto's story for nothing Boruto has to learn to follow what his father says.
And if we really want to be cynical, we could say the moral is this: Sell Out. Forget about your principles and do what others want you to do. Keeping things going for as long as possible is better than fixing things and ending the story.