What you can do is follow the links for downloading the firmware from Adafruit mintioned in the article. You end up at -> https://github.com/Microsoft/uf2-linux
Where it states (emphasis mine):
UF2 Flashing for Linux
This repo contains scripts and patches to build a sample Linux image based on piCore for the Raspberry Pi Zero. The image is meant to boot very quickly (currently at around 7s), and expose a USB mass storage device (pen drive), which can be used to program a Raspberry Pi Zero with UF2 files, usually generated from Microsoft MakeCode and in particular from MakeCode Arcade.
The image was tested on a Raspberry Pi Zero Rev 1.3 and Zero W Rev 1.3. It could theoretically work on the original Pi A/A+, but wasn't tested. Other models lack the OTG ID pin, and thus cannot be used in USB device mode.
So the RPi3 cannot be used with the Makecode software
indicated (at least in USB mode. Maybe it will work as a game without this feature on RPI3 - I don't know. maybe download and test it before building?)
That doesn't mean the RPi3 could not be used with this cardboard arcade controller - You just need to use games that can recognise the buttons and switches through the GPIO pins.
A quick Google search lead me to this example -> https://www.crackedconsole.com/2019/03/ ... stick_rpi/
So maybe you could use Retropie with this Arcade controller on a RPi3, just not MakeCode?
(Disclaimer - I'm not really familiar with this controller stuff myself, but hope the above gives you some ideas of where to look for further info)