I think there is good and bad. As a "horse person" I have just casual knowledge of thoroughbred racing, but have a but more experience with harness racers (Standardbreds). I have very mixed feelings about that particular sport. I used to own an off the track standardbred, and hung out in the barns/saw him race a few times before they sold him too me. He had suffered a ligament injury and the owners decided to give him MUCH less time off than was recommended for the injury because they didn't want to lose the whole racing season resting him (their explanation, not my assumption). He performed poorly after they started racing him again, despite them dosing him with NASIDs before the race. These owners were not bad people, and they seemed pretty well respected in the barns at at tracks I spent time at, but this just seemed to be the norm.
After getting my gelding home we started attending to his leg (the ligament in question had bowed out sideways), and with about a year of recovery and treatment he was sound, and now spends his days as a pleasure riding horse for a lovely family. His alternative would have been to be sold to the Amish, used as a carriage horse until his injury caught up to him, and most likely sold at auction to meat buyers-most of the Amish are not going to feed a horse that's just sitting in recovery for a year.
Also, it doesn't seem that Standardbreds have the same post racing opportunities that thoroughbreds do-TBs are more popular as sport horses and much of the horse industry is not well informed about STBs. After buying my gelding I had numerous people who had years of experience with horses express surprise that I intended to turn him into a riding horse, and had a well established trainer tell me, "You know those horses CAN'T canter, right?" (they are discouraged from cantering during race training so extra work has to be out into cantering when training as a riding horse, but they are certainly capable of it).
The bottom line is that in any animal activity were money and egos are on the line there are going to be abuses. The hope is that responsible people within the community step up and self police before said abuses cause outside entities (federal government) to become involved.