You could do that and many do to avoid updates but often sign back in to get updates. As much as we hate many of these updates they are sometimes necessary for security etc. My suggestion is keep updated. I keep all my androids signed in with google for this reason. There was a time I stayed logged out but I find that a pain. Using a vpn the various apps cant see what you are viewing and to be truthfull all they want to do is feed you ads. With an alt launcher they cant and thats amazons reason for blocking other launchers and im surprised google hasnt got into the game more but you can bet they will clamp down eventually with certified boxes. Just my 2 cents