I honestly would not be surprised if Google added some form of ads to Authenticator. The only reason they likely haven't is that it isn't the type of app that is used frequently or for long sessions.
Microsoft has been pretty shameful with ads in Windows recently, but they also give away OS updates for free. Someone that purchased Win 7 has been able to go all the way to Win 11 for free (assuming their hardware is supported on 11).
Microsoft has been pretty shameful with ads in Windows recently, but they also give away OS updates for free. Someone that purchased Win 7 has been able to go all the way to Win 11 for free (assuming their hardware is supported on 11).