The difference between Miro and Deku is that Miro was preparing his whole life, even while he, also like Deku, was bullied and made fun of for his "useless quirk" or in Deku's case lack thereof. Told his whole life that we would always be useless and a failure, but the difference is, Miro actually made something out of his situation, he worked with what he had and made something of himself. He worked every day and night for years to become the number one hero so he could save people, and be their hero. The disappointing thing is, Deku grew up with relatively the same conditions, and yet, he never looked to what he already had and toned those skills and talents to make something of himself. He could have been an amazing analytical hero or a detective, with his observation skills over the years accumulated his knowledge was great, his shortcoming was the fact that he never looked into himself and saw the ability he already had, he wasn't able to help anyone else if he didn't have confidence in himself. True, he was bullied and probably had self esteem issues, so do I, I've been bullied, have extreme self esteem issues, self confidence is down the drain, depression, anxiety, panic attacks, and so much more, but that didn't stop me from trying to do something about my situation instead of being a sitting duck. Selflessness isn't running into a situation in which you know you'll die to help someone else, especially if you still don't stand a chance at helping someone else, in order to be selfless you must have something to lose. Deku isn't selfless, he's naive, and recklessly puts himself and others in harms way, sure he's got the best intentions, but he cannot continue on with his idealistic visions for the future and mindset. He'll end up either hurting himself (already done multiple times), putting others in danger (also done multiple times), or losing someone (lost Bakugo to kidnapping and almost got kidnapped with him because he kept reaching out to him even when bakugo said not to because he knew Deku wouldn't have a chance). I would be satisfied with Deku becoming a professional hero, as long as his naivety and idealistic mindset are changed, and if he is able to save people, not just by taking down a villain, but by fixing the society or making small differences, try learning finance and skills for amendments to the laws instead of how to take down villains that were born out of the same societal issues that should be repaired. I know it's just an anime, but I do not wish for anyone I know to think that the idealistic mindset is more worthy or more infallible or will change everything for the better in a society that is crumbling under itself is true and will not listen to reason and logic. I speak out of concern both as a writer, and as a reader, and as a empathetic individual, as well as an intellectual with physiologist like tendencies and societal viewpoints. I am not attempting to invalidate your opinions or stance on this matter, I only wish to bring to light the flaws I have seen within the character's creation.