iOS isn't completely supported by HealthKit, false means no, true means user has approved or declined permissions.
In case user has declined permissions read will just return empty list for declined data types.
It's not advised to call await FitKit.read(dataType) without any extra parameters. This can lead to FAILED BINDER TRANSACTION on Android devices because of the data batch size being too large.
If you're using more than one DataType it's advised to call requestPermissions with all the data types once,
otherwise iOS HealthKit will ask to approve every permission one by one in separate screens.