expo-google-sign-in documentation

reading the documentation (https://docs.expo.io/versions/latest/sdk/google-sign-in/) it is written that expo-google-sign-in can not be used in the expo client. And few lines later “For managed apps, you’ll need to run expo install expo-google-sign-in”.
From my understanding managed apps is to be used with the help of client expo (and that’s so convenient !).
So what do I don’t understand?