GPS or Wifi could easily be attached via USB, you don't need GPIO for that. The huge benefit of GPIO ports are all those things that DON'T have standard ports l

GPS or Wifi could easily be attached via USB, you don't need GPIO for that. The huge benefit of GPIO ports are all those things that DON'T have standard ports like USB: sensors (temp/humidity/air, radar, …) or controlling lights (e.g. LED strips) or other basic electronics that you wire to your SBC. Really the GPIO pins are what makes SBCs so great for me... a smartphone is just a closed-off portable computer with very limited built-in sensors.