Let's be honest here, ash is literally goku ( i know i've said this a dozen times already but people still don't get it ). These characters are kept oblivious for a reason, because the target audience viz pre-teen boys care little about emotional affairs with girls and more about finding their own sense of identity. That’s why identity and the effort to become stronger (that is, carve out a place of meaning in the world) drive these shonen protagonists.
if a story’s protagonist is brash, impulsive, and dumb, it’s easier for boys to identify with them and laugh at them. Dumb and emotionally dense characters make the viewer feel smarter than the character as opposed to feeling inferior as they would with the knowledgeable, thoughtful character. All of this increases the likeability of the protagonist. Not to mention boys often wish they could act out as shonen heroes do
Now pull this idea toward love. We don’t want a capable protagonist for love. If he is brain-dead or bumbling with the ladies (I am going to stick with heterosexual relationships), the audience can again sympathize, identify, and feel superior to the character. In short, the character becomes more likeable. Relationships are awkward, especially in their early phases. Characters that struggle with this awkwardness provides a sense of relief for boys who’s interest in girls is just awakening