That's... That's literally the point guys... Koichi made a mistake that lead to Jotaro getting hurt, so now he's taking what he learned from the experience and using it to fix it... And growing as a person and character?? That's the whole bloody point of this storyline?!! Hello??!!
Also, what is this "he can't do anything on his own" thing, he very much can and we've seen it before... He's not my fave, but I honestly don't understand all the hate he's getting here :/