GrapheneOS doesn't automatically connect to Wi-Fi either unless you enable the option. It also has per-connection MAC randomization enabled by default so Wi-Fi is essentially anonymous when you use it anyway.

> you can't tout it *and say it's privacy preserving.

Why? Sandboxed Play Services has no special privileges on GrapheneOS and thus has the same level of access as any other app. How can it invade your privacy if you don't explicitly give it access to private information?