In "The Scarlet Ibis," what is Hurst suggesting about how conflict and conformity affect the outcome of the story?

In James Hurst's short story, "The Scarlet Ibis," the tragic outcome of Doodle's death is a result of both the narrator's desire for conformity and the conflict that ensued between Doodle and the narrator based on this desire. 
Doodle knew he was being pushed beyond his limits. Brother, the narrator, had rushed him to Horsehead Landing for more training, and that exertion by itself was extremely difficult for Doodle. Brother doesn't pay much attention to the signs that Doodle is giving him that the exertion is too much. He is completely focused on his goal. His goal is that Doodle will be like every other boy in his class, thus conforming to society's expectations of what a boy his age should be able to do. Here is the textual evidence: 

"Time was short, and Doodle still had a long way to go if he was going to keep up with the other boys when he started school. The sun, gilded with the yellow cast of autumn, still burned fiercely, but the dark green woods we passed through were shady and cool. When we reached the landing, Doodle said he was too tired to swim."
 

During this scene, a thunderstorm blows in suddenly, darkening the sky with black clouds. There is lightning striking, and the boys have to hurry home to avoid the storm. The following quote reveals the narrator's attitude toward Doodle as he does not live up to Brother's expectations of him in the training program.  

"Doodle was both tired and frightened, and we he stepped from the skiff he collapsed onto the grass, sending an armada of fiddler crabs rustling off into the marsh grass. I helped him up, and as he wiped the mud off his trousers, he smiled at me ashamedly. He had failed and we both knew it, so we started back home, racing the storm. We never spoke (what are the words that can solder cracked pride?) but I knew he was watching me, watching for a sign of mercy." 

Brother explains his disappointment in Doodle and how it hurt his pride. His pride had been his motivation for teaching Doodle to walk at age six, and for pushing him to become the same as every other boy in his class. His pride is what causes him to want Doodle to conform, and also what causes him to leave Doodle in the rain. Brother is fully aware that Doodle is frightened of being left alone. Racing back home faster than Doodle is capable of going is Brother's revenge for Doodle disappointing him. But his child's mind doesn't understand the tragic and irreversible consequences that will ensue.