> without any garbage running on it

That sounds like a utopia we've passed by on our way here. Maybe it's possible to make such a dedicated hardware device when the digital wallet becomes available for a (mobile) linux distribution or a degoogled android. Let's see when the phone manufacturers think that's a good idea to lobby for

I'm cynical about the whole digital wallet idea because of this. Not that it's not useful, but it's tying your mobile surveillance unit and browser history to an identity on hardware that you are not meant to control