The App Tracking Transparency refers to a tracking pixel to understand user behavior across apps.
So if I visited one app, I could then receive relevant ads in another app based on my behavior. It does not have to do with storing user information that has been provided via input from the user!
When reviewing your app in the store you are offered the option of if your app uses tracking. You can say NO to this unless you have incorporated some specific tracking service into your app.
We do not & have not tracked the user information that Apple is referring to when they are talking about tracking.
In any of our AdMob components, we are not inserting the UUID parameters that Apple is referring to when they talk about App Tracking Transparency — so even if someone said you could use their data to track them, we do not store that information, making personalized ads impossible (you can still receive generalized ads without the ATT turned on).
I hope that provides some clarification!