Yeah, "Game that ran on an 8MHz Arm in 1993 running on a 40MHz Arm in 2021" wouldn't have been as attention-grabbing.
So the OP is not entirely wrong: they ported a game played on a 16.8Mhz system with 256kb of RAM to a 80Mhz with 108Kb of RAM.
The writeup explicitly says «we could trade off some computing power of the 80Mhz Cortex M33 to save memory»