The simple version is that the Raspberry Pi Pico is not officially supported by the MakeCode Arcade platform. You can get it to work, though.
As for whether it will run “a large 3D game,” it might. The RP2350 (the processor for the Pico 2) has a little more horsepower than the Atmel chip used in the Kitronik Max (150 MHz vs. 120 MHz), but you might not see an appreciable difference.
If you want a major boost in performance, you may be better off using one of the full Raspberry Pi platforms (e.g., something based on an RPi 4 or RPi 5).