A good trail horse should know how to take care of his legs. If you compete in NATRC competitive trail rides, wrap, splints etc are not allowed and their horses do just fine.
I've ridden my horses in the wilderness of the west for years and never had more than minor rock bit from trail rides. It's not like a reining competition where you are asking them to spin and have a high chance of stepping on their own legs.
Unlike performance events like barrel racing that last 17 seconds or a 2 minute cutting run, A trail ride or endurance race can last 5-6-8 hours. That a long time to have something on their legs that holds in heat and can capture and hold sand, water or grit against their skin. You are better off with no protection.