If they had told users (which they should have done) it might have lead to even more sales of new iPhones. Yes, some users would have replaced just the battery.

If they had told users (which they should have done) it might have lead to even more sales of new iPhones. Yes, some users would have replaced just the battery. But many others would have replaced the phone entirely, among them people who would never have noticed any slowdown from throttling.