He literally lead shigaraki away from everyone and acted as bait, he was braver than most of the remaining heroes on the scene at that time
do toddlers have six-pack abs?
also, a boring character is one without flaw. if a character has no internal or external conflict and is completely perfect, that's a boring-ass character. deku had to earn his power through 10 months of rigorous training.
the acting like he's weak is because of the time he spent as a child with bakugo, who thought that everyone, especially Deku, was far below him.
"He’s so one note i could leave a single word and describe him" you can do that with anyone. it won't give you all the info for anyone though
when has he gotten offended, other than when villians do f**ked up shit and treat it like a joke
he's trying to turn the insult into the name of a great hero because he's so used to that name that at some times he forgets it's derogatory. kind of like how me and my nerdy friends wear the title of nerd like a f**king crown
your last point is correct