I mean it didn't stop a lot of people from clicking through "scary warnings" to install Facebook's VPN app that hoovered up their data. I think you are vastly underestimating what people will go through for a minor benefit to themselves (in the case of the VPN it was low dollar amount gift cards).

FB won't remove their app from the app store but instead will add a new feature or offer a perk that is only in their side-loaded version and it will drive users in droves to install it.