Sorry this got long but imma post anyway LOL Please note that im generalizing and we all know every situation and horse is different. Dressage footing usually isnt soft BTW...its usually kinda hard and gravelly IME. Kinda weird considering the strain these horses put on their legs at higher levels. Heck, I PARKED a truck and trailer on the dressage rings at FENCE LOL...It barely had tire tracks.
IME horses that are shod too early in their lives and stalled alot without lots of movement or are neglected as babies with their hoof care and allowed to grow underrun heels and long toes from the get go (NO you can't just turn a baby out till its a yearling without hoof care because it doesnt "need" it. I beg to differ! Babies need hoof care just as much if not more than adult horses when the foot is at that critical developing stage ) tend to need shoes/protection as adults because they never fully developed their foot.
Consider this...high level (IE expensive) horses usually live very cushy lives in barns with lots of shavings and lush pastures with lots of feed and are kept too fat for their own good as youngsters and even down the line which are not conducive conditions to developing healthy well developed hard feet. A young horses foot is nowhere near mature just like his body when we start riding them generally at age 3 but much younger for racehorses. Their feet grow and mature as long as their body does, which in big WB types means till 6 or 7. If they are shod young and kept stalled and from enough stimulation to turn the fatty baby Digital Cushion into hard tough cartilage, they will be stunted in hoof development.
Some are left locked into tiny shoes that fit as a baby (how many farriers short shoe so the horse wont overreach and pul shoes? I very seldom see properly set shoes these days) and recieve poor farrier care in general setting them up for long term problems also. Or they are simply used too hard for where their body is at developmentally also. Again thinking racehorses but we all know this. Not only are their skeletons not mature but their feet are very immature also and being asked to stand up to extreme conditions. Again its just asking for problems as the immature hoof capsule and baby fat digital cushion squishes under the force.
I look at it like head binding babies. If you apply force or constriction while the baby is developing and still "squishy" for lack of a better word, it deforms even the very bone as the creature grows. If left go on very long, it can affect the whole foot all their lives. IMO the same horse. If he were left barefoot and allowed to recieve lots of movement and the stimulation of harder terrain till his body and skeleton were mature might have developed a completely normal and adequate hoof that could have gone sucessfully barefoot in most situations, except perhaps the harshest.
This is my experience and my observations based on raising and trimming babies and watching them develop as they grow with and without shoes. Anyway....sorry for the novella...just food for thought. Long story short, IMO, young horses whose feet are actively developed by their owners just as their bodies are developed do better and are more sound over the course of their lives are are more able to go barefoot as adults even over terrible terrain. If you have to shoe a youngster, consider a flexable shoe and promptly remove it as soon as possible and TURN THE BABY OUT!
I used to believe most horse's feet could be rehabbed to being sound barefoot if given the proper time trim environment and so forth, but now I believe that shoeing them too young, of course shoeing them improperly and leaving shoes on young horses long term can really set them up for needing shoes their whole life. They just can develop the foot they were meant to have and it is essentially stunted or damaged for life. Again JMO based on my observations. Take what you want from it.