I disagree, Its a big sport, so people like PETA or other groups really notice when a horse dies, they just don't so much in the other horse sports because most of them are smaller.
IMO its not that bad. Like the others said, horses are dying everywhere, and I bet the whole sport is trying hard to make it safer for horse and rider everyday. But there will always be risks in every sport.
Another thing is, its just as dangerous for jockeys, but no one really notices that. And it is the jockeys choice aswell, but if you put a horse that was bred for it loose at the starting (or even in the starting gate) it would run, most, if not all, the horses in a sport like that love it, and why wouldnt they? Horses like to run, they like to jump aswell (most.)
I don't see a problem with it.