There are hundreds of cases of kidney failure in cats and dogs EVERY week, all the time. And a good portion of the increase during the pet food scare is attributable to nervous owners taking their pets to the vet, even when they had no symptoms or had symptoms so mild that the owners wouldn't normally have taken the pet to the vet. A lot of these animals just got an early diagnosis of pre-existing kidney failure, that they would have gotten later if it hadn't been for the pet food scare.
Certainly there have been a number of deaths and permanent kidney injuries caused by the tainted pet food, but there have also been a lot of pets diagnosed much earlier than they would have been, whose lives are going to be much longer and healthier than they otherwise would have been, because of starting treatment very early in the course of progressive kidney failure. And much of the normal background rate of acute kidney failure from common household products (antifreeze, organophosphate insecticides, etc.) and house and garden plants, is no doubt being attributed by owners to tainted food when that wasn't really the cause.
You are right, but not in very young dogs and cats... also, the crappy food is one reason dogs and cats are suffering renal failure at younger and younger ages.. and what do vets do — limit the protein when that is exactly the wrong thing to do (as evidenced by a researcher at of all companies Purina a few years ago and presented at a seminar on pet health).
While some of what you say is true, I sincerely hope you aren’t trying to minimize the true scope and magnitude, not to mention the overall significance of the root issues here. And there is a clear difference between early detection of chronic kidney failure vs. early detection of acute kidney failure.