This world needs Ultron. Peace in our time, imagine that.
You want to protect the world, but you don't want it to change.
Tony's flaw is his excessive arrogance and pride, which presents itself in the way that he relies only on himself to save those around him.
I tried to create a suit of armor around the world, but I created something terrible.
His pride in his intelligence, ended in him creating Ultron and other lethal weapons.
I am Iron Man.
Tony's actions ended up killing a lot of innocent people and putting the Earth's future in peril.
When Tony sees Wanda and she blames him for everything, showing him a vision, he realizes that all the chaos that's been happening, started because of his own creations. This making his anxiety more prominent.
Tony takes the infinity stones from Thanos and loses his life along with everything he had.
His journey ends with him dying as he restores the balance of the universe.