I find this line of thought interesting. Looking at other Shonen protagonists, I rarely see much if any character development. They are paragons of good, and usually have very little in in the way of character development. But I don't see people complain quite so much about it -- which makes me wonder why it's an issue for Izuku. I personally think that Izuku had a lot of potential in the beginning to expand as a character, but it's pretty clear that Horikoshi is going for him to be a paragon of good also, which is disappointing to me, but it is what it is. I personally don't see how Horikoshi could give him good character development after the opportunity has been squandered, but maybe he'll surprise us.