I'm glad we agree about something, GG13
I found an elderly article in New Scientist that discusses the running of 2yr olds. It ends up being a bit inconclusive but it certainly does make it clear that ultimately, it's the money that counts, not the welfare of the horses.
www.newscientist.com/article/mg13718652-600/
I'd take issue with this, Luca Carmani, one of Britain’s leading trainers, acknowledges that there is a long-standing debate about the merits of racing two-year-olds, but says he is unaware of scientific evidence to support claims that early training is harmful. He says galloping does not come naturally to horses, so they have to be trained to run fast: and the earlier, the better.
That's nonsense. My daughter's cherished horse, homebred for eventing, was galloping around the field from the start! And you only have to see a group of horses turned out with a 'newcomer' having a good old high speed hooley round the field. Galloping is a natural pace.
Also, jumping is not unnatural. Horses mostly don't bother in the wild, but they jump if they have to. Training a horse to jump is just building on its natural ability; there's no cruel forcing involved. Same for dressage, which refines a horse's natural paces.
Another startling statistic from the article is that about 8,000 foals are produced annually for racing. Very few of them end up on the racetrack. Nor do many of them end up as pleasure rider's much loved 'pets'. More likely to be dog food or sent for human consumption in Europe.
I'd also take issue with GabriellaG. Foals aren't born late in a year. Most foals are born in late winter/early spring because they need the lush new grass for growth and development. To feed substitutes for grass to a foal born in the autumn or early winter would be far too expensive. So, as the article points out, they are mostly about 18 months old when they go into training.