stefan10022 I'm thinking of installing GrapheneOS, but I'd prefer to use the google apps for basic functions of the phone (ex. Google Photos, Gboard, Clock etc.).
The GrapheneOS team works hard to support that usage model!
stefan10022 Does disabling network permissions for these apps eliminate all of the privacy concerns regarding these google apps?
In practice, maybe. In theory, not really. Because of IPC, disabling network access for the apps but leaving it on for the Google support code means the app and the support code could collude to share your data with Google. There are reasons to expect that does not happen in practice, but the OS does not prevent IPC between apps in a profile.
Meanwhile, the Google apps are not really designed to work without network access. Even if they work now, some future release might not work as well.
stefan10022 Why would I choose to use the inferior (in my opinion) AOSP apps instead of the gapps but with disabled network permission?
Some people prefer to run code they have the source for (and can thus improve and extend).