The Banana Pi BPI-M7 single board computer is equipped with up to 32GB RAM and 128GB eMMC flash, and features an M.2 2280 socket for one NVMe SSD, three display interfaces (HDMI, USB-C, MIPI DSI), two camera connectors, dual 2.5GbE, WiFi 6 and Bluetooth 5.2, a few USB ports, and a 40-pin GPIO header for expansion.
And it wouldn't have gpio, would require at least a square foot of floor/desk space, and it would cost more to run. Price. Size. Gpio. Nobody is running their remote controlled car with a cabled desktop sat on it.
If you just need GPIO for low level electronics there are 20$ SBCs that get the job done. No need for a full RPi5.
USFF boxes are quite a bit smaller footprint than 1 sq/ft, about 7"x7"x1.4"
If you're running a remote controlled car you want something way down the power scale like as ESP32 or even an ATTiny + radio HW.
Mind you, I don't disagree with your actual point, I just think the example you used wasn't correct.
Not sure how much more it would cost to run. If you only really talk about stuff a pi can do as well, you wont be maxing out your cores. You will use a bit more maybe. Nothing sort of whatever you only really keep in mind for monero mining.