The SmartThings Link contains only the Zigbee and Zwave radios, the core SmartThings hub firmware is built into the Android OS image that is released by Nvidia. Unfortunately, updates to the SmartThings hub firmware requires business level action between Samsung/SmartThings and Nvidia that is out of the control of the hub engineering team. We cannot release hub firmware updates independently of Nvidia’s image updates.
I understand your concern, it is no doubt frustrating to have equipment with firmware that does not support the latest features. It is possible the SmartThings hub firmware will be updated on the Shield in the future, but I do not know when this will happen.