It’s undoubtedly tied to the phone with is tied to the owner

People report that it works even on grapheneos with sandboxed google play. My guess there's some fingerprinting going on, not necessarily that they're tying the account to some account id.

Well yeah. But if you care about anonymity on that level there are ways around that (i.e. buying in cash and creating the account using public WiFi).

How is your phone tied to you? You bought it through GOogle store?