I noticed that Brazier was very passive, even deferential, to Kszchot when he passed just after 600m. It appears that once he knew he would be DQ'd anyway, he just caved in mentally. He was just going through the motions. A true competitor would have been mad at himself for the mistake, and probably run a PR on pure self-hate.
I'm not sure we will see the "killer instinct" with this kid, even as he matures. When you cave in at a major performance like this, it leaves damage. A great coach can help an athlete through this, but I am not sure that Brazier has that situation.
Watch the video:
Murphy and Harris and Berian are far more aggressive. I agree that outdoors Brazier is going to put up some fast times, but he will also be smoked by Murphy who has the desire and outright meanness to do well in big races and the talent to break the AR. And Harris may catch Brazier this season, as flat footed as he is. Harris also isn't shy about cut people off and tossing elbows if one looks closely at his races. Berian is just plain tough. Brazier is just as talented or maybe even more so as anyone other there, but not as competitive as the three US guys I mentioned, never mind someone like Kszchot who has battle scars from rough international competitions.