I'm saying it doesn't matter if they avoid a brand if the alternative is that they will buy a knock-off. Neither option represents any value to the actual manufacturer- avoiding negative PR from people with knock-offs might actually be preferable.
I know people click through warnings. If that warning could keep them alive, as a dev I'd better do something that'll get their attention.
Also, if they only softly bricked these phones the counterfeiters would just click-through the warnings and sell the phones that way. They have to essentially burn them, for the safety of people who need to be their customers.
If you want a regular phone running whatsapp, use that.
If you didn't want that, there were cheaper phones - even counterfeit.