The Dragino gateways only have 16MB flash storage, which with the Dragino firmware is just enough for installing the MQTT Forwarder.
Porting the GW OS to Dragino would require a bit more work, because their own firmware is still using OpenWrt 18.X, where the GW OS is using 23.05.5 (latest stable). I already reached out to Dragino if they could provide support for their devices for OpenWrt 23.05.x. Once they can provide that, it should be fairly easy to port the ChirpStack Gateway OS to Dragino gateways and maybe create a bit more space such that it can be bundled with the Gateway Mesh stack (I can’t confirm this will be the case).