What is the purpose of the Ethernet/IP and Modbus TCP I/O Cards? You can already access E/IP and Modbus TCP from Node-red or python with a standard Raspberry Pi.
True. However these modular gateways are ODVA-certified and have gone through all the mandatory testing (surge/burst, shaker, climate chamber), so they might be the preferred solution in environments where certified devices are required, be it only for compliance reasons.