Whether it was the right decision can be endlessly debated. Obviously those at the time, including the boys, thought it was.
I doubt anyone actually thought sod the boys do it for the crowds.
For some people, including children, having an act of bravery to perform for your loved one gives you courage to get through something hard, with a sense of drive and duty to do something for them. And will always have a sense of pride/ gratitude/ satisfaction that they did a hard thing to demonstrate their love for the person they lost.
For others they need to retreat and be cared for, they seek comfort and not action.
There isn't a right or wrong and the current view that comfort is the only way to help someone through difficulty is as flawed as the old stiff upper lip.
There are different ways through and decisions should be taken on the basis of the personality, needs and wants of the people involved.
Maybe it was the wrong thing for Harry, but he says he's glad, suggesting it's certainly not a straight forward right/wrong decision.