That may be the case but I went down this rabbit hole and after over $125 worth of parts and essentially rebuilding the entire toolhead, the problem repeatedly come backs. Bambu was no help but they were sure glad to take my money.
The specific post I was referring to all appeared to have been removed by Bambu. I know because many of them I posted and they are gone. There is one similar post that still stands that may give you some troubleshooting ideas before spending money. Try some of those out first and then, yes, buy a replacement fan since that is the cheapest diagnostic step, but be prepared to go down the rabbit hole I did.