The "debug" option removes the code optimization so that the single step debugging would follow the actual source code. Optimized code execution is important for the MCU and it has been verified with this experiment.
The firmware built with "debug"should not be used on final product.
For development "snip.udp_transmit-SN8000x-FreeRTOS-LwIP-debug download run" could be used. For final product "snip.udp_transmit-SN8000x-FreeRTOS-LwIP download run" should be used.