I don’t think anyone involved or watching liked seeing horses killed, but it is a fact that a broken leg for a horse is still near impossible to repair at this time and too great an emotional trauma for any horse. (In another 10 years stem cell/bone rebuilding tech just might make it viable).
Putting the very demanding Aintree Course aside for a minute, hunters and steeple-chasers actually like jumping and racing, and some horses are quite competitive even without a jockey (just watch some of them jump the fences when they have lost their jockey).
The debate should not be over whether Hunt or steeplechase races are evil, but whether Aintree is too demanding. I’m pretty sure that any accidents on the course will be thoroughly investigated and further steps will be taken to reduce the future probability of such accidents. IMO no-one will have viewed Aintree as a gladiatorial event in which humans and animals are killed and injured. Apart from actually liking their animals, the cost of ownership and upkeep/training of a horse are far too high for any owner to lightly throw away any horse’s life just for public entertainment.
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