Goku as a kid seems like a kind of normal rural naive kid, like the dumb things he does you get it why, he's a kid that lived alone with his grandpa in the woods, so there's a logical explanation, and his behaviour is comprehensible, in no way i would say kid goku was a dumb kid, he was a much more logical character, in lots of stuff he was even smart during the og dragonball, and he had a more human side, he looked like a kid, like he really loved his grandpa and care about friends, talk, laughs, hang out etc.
If we compare to addult goku that's a battle junkie, dumb in most stuff except battle, and he's irresponsible with only training and battle on his mind. And is insensible to say to his family and friends "gonna train in heaven for 7 years see ya", and not even start about how he made some very dangerous decisions like letting enemies alive so he could battle them later and stuff.
I think akira in dbz created an archetype for goku, that got stick with what goku is "dumb obsessed with fighting", and that what goku has become.
I know people will say its a battle manga, but there's still character development in this type of manga.
If we compare to addult goku that's a battle junkie, dumb in most stuff except battle, and he's irresponsible with only training and battle on his mind. And is insensible to say to his family and friends "gonna train in heaven for 7 years see ya", and not even start about how he made some very dangerous decisions like letting enemies alive so he could battle them later and stuff.
I think akira in dbz created an archetype for goku, that got stick with what goku is "dumb obsessed with fighting", and that what goku has become.
I know people will say its a battle manga, but there's still character development in this type of manga.