To do so would really cripple them. To stay active they must be active.
Good dogs can throw a dysplastic pup.
The dogs which have it and the handler who owns them have done nothing wrong. It's just a fact of their lives. Watch your dog's weight and conditioning and keep both at their optimal peak. A dysplastic dog never gets an off season for conditioning - to do so could mean never getting back to that higher level again. Develop an exercise program that has other activities besides agility.