I heard in Japan that the age group for them to watch Boruto is around the age for kids to watch the show with there grandparents. So I think that's like the age of 6 or 7 and this was confirmed by Masashi Kishimoto as well when the show was in production.
But for adults I can see that this anime isn't for a little kid to look at especially when Boruto and other characters swears with curse words.
I also found out that Kishimoto say that he wants for it to be more happy and fun, something that younger viewers can really enjoy. He wants it to be distinct from how "Naruto" turned out because as the original series went deeper, Kishimoto said that it got "more introspective and darker".