@jmarcelino/ @Epyon, TTN GW designer here Your concerns are valid and complicate the cert process. A co-existence protocol can be implemented if it is deemed necessary.
The ATECC508A will be activated later to provide an additional layer of security ( since firmware over the air updates are difficult/wasteful/impossible with LoRaWAN). Updating physical hardware over the air is still difficult in these days and ages therefore we included it already
The PIC24 on the gateway module is there for house-keeping and as a wrapper around the SX1301, making it a certifiable module. It also provides the USB interface, but initially only UART is enabled. But its not a packet forwarder - the PIC32 handles that.