We really need to move away from the idea that a user having control over his/her device is insecure.

I can use online banking and paypal with windows logged in as administrator or GNU/Linux logged in as root[0], why shouldn’t I be able to use google wallet pay wallet with root?

[0] yes I know you shouldn’t log in as root, but that doesn’t change that you can do it.

Does rooting your device make you the root user or just gives you access to superuser utilities?

In linux systems the root user shouldn’t be used for daily use, you just make an user account with permission to use sudo, doas or su.

If you root your phone, at least with most tools, you don’t become the root user. Apps that use root access have to request it, and you’ll have to allow it in the root tool you flashed.

Example pop-up from SuperSU:

So google is lying about rooted devices, they seem as secure as an OEM letting an user sideload apps or google themselves letting malware apps inside their store