QCI for Default Bearer

Hi Experts,
For LTE/5G NSA QCI, what is the operator/vendor consideration to choose between QCI 6/7/8/9 for default bearer though we know better QoS for QCI 7 as per below table?

image

In my experience Qci8 or Qci9 was used for default bearer.
But this changes in different countries and networks.

Default bearer has to be non gbr and can be used from 6-9 any.

We map QCI 9 as default bearer for general customers and QCI 8 for ICR users.

Qci 9 is default bearer and rest 6-7-8-9 operator can use for special plan or to priorities customers over qci9.

Ok, So does it have anything to do with APN settings in the device?
Different apn for privilaged user class or so?
Or is it based on unlimited plan users with one QCI and truncated/throttled plans after definite payload or so?

Not sureā€¦ but I think not dependent on User devices APN.