iOS is not deleting app data even if the app is uninstalled

as per discussion here

https://www.reddit.com/r/privacy/comments/lee6b8/fyi_ios_is_not_deleting_app_data_even_if_you/

the apps basically able to use /abuse keychain as super cookie .retaining some user information after uninstallation.

For example take Tinder app. if uninstall the app it still able to retain login information. and upon reinstallation the user automatically able to login .

If user gets banned by tinder app . and tries to create new account. the user account gets banned because there information is retained in keychain. and the app de facto able finger print the device.

The apple has been forever pro"privacy" but in fact if it was actually pro privacy it would actually allowed user to have root access to their device to control which data can be retained. and control how app can behave. it' just privacy theater. !