Ixirup GrapheneOS does indeed give the potential to use many of the Google apps relatively privately, at least when compared to stock Android. There's nothing special about Google apps in this sense: they can't do anything that other apps can't also do on GrapheneOS.
It's still worth thinking carefully about which apps you choose to install, and minimizing the number of permissions you give to the apps you do install. GrapheneOS helps to improve things with invasive permissions by development of scoped features. That applies to any apps, Google or otherwise.
Your comment appears to engage in an overly simplistic broad brush statements. Users can still absolutely hand over private information to apps on GrapheneOS, there are situations where they might want to, and others where users will want to avoid that. For those situations, GrapheneOS gives users the tools to have more control.