Well, I've met too many, read the stories of too many, felt too many teachers and students with wrecked bodies to agree with you. Shoulders, a mess, backs a mess, knees a mess, a couple with hip problems.
If you want to argue percentages, it still doesn't change the model, the percentages would tell you that repeated falls -no matter how good you think you are-are not good for you. Then again, so says every PT and sport therapist I know, and for some strange reason the ones who were damaged know as well.
Taking years of impact doing ukemi can certainly injure or damage your body.Knees /shoulders and hip s are usually the areas that cause pain. Suwariwaza in particular does your knees in.The occasional Shiho Nage wrenched shoulder/elbow joint also can be a pain[literally].Your body has to last you the rest of your life, so you have to use your head and look for ways of lessening the chances of damage to your body.Of course the young turks think they will be the same at 75 as they are at 20 years old. In their dreams . Hope you are well.Happy Easter to one and all. Cheers, Joe.