For the reference implementation that will not actually be deployed as an official solution so far, yes. Although you could also go with an Apple account.

In fact, I don't think you technically need to be signed into a Google account for Play Verification to pass, though many phones do make completing the Google sign-in a requirement.

> For the reference implementation that will not actually be deployed as an official solution so far, yes

...or the IT-Wallet which is currently deployed, and who's developers stubbornly refuse to remove the requirement.

> In fact, I don't think you technically need to be signed into a Google account for Play Verification to pass

And you're wrong, Play Integrity checks that your phone's account really downloaded the app from the Play Store, and so requires a (signed-in) account.

> many phones do make completing the Google sign-in a requirement

I'm not aware of any such phone, although they sure make it seem like it's a requirement

> Although you could also go with an Apple account

With a cheap, and very open and privacy-respecting, iPhone