Apple compared the M1 Max to a 3080m. 4x the GPU cores and up to 8x the memory makes a difference, and it wouldn't be at all surprising to see that their numbers are accurate.
No one has explained what you got wrong, so in case anyone reading this is still confused, Apple compared an M1 Max to a 3080m. An M1 Max's graphics card is ~4x as fast as an M1.
Do you have first hand experience with this? I do . We play WoW on MacBook air M1 and it runs fantastic . Better than my intel MacBook Pro from 2019