You do realize in japan teens/adults read manga and watch anime?It's widely known that teens/adults watch particular anime in other countries, as well.
So realistically speaking, it isn't necessarily JUST for kids...just CHILD APPROPRIATE.
However, boruto is a little too childish to watch, at times.
People of older crowds are "Distinct"(while some are just childish)...has everything to do with the "type" of anime.If it's action, well, people wanna see ACTION or a good plot development. People want quality, especially if they grew up watching anime. I will say, I don't have patience for a lot of anime...I'll watch DBS and some canon episodes of Boruto, but that's about it, for now.