Emulating a 6809 in a slow ARM mcu

As a thought experiment I’m wondering about a different approach to Project 8821. The STM32F407VGT6 is a 168MHz ARM Cortex M4 processor with plenty of flash and RAM to handle Joust. Could it emulate a 1MHz 6809, drive resistor-ladder analog video, and output sound? I bet the answer’s yes.