I just watched the video and people would have gone nuts over the improved graphics in 1996. The other commenter is right that the thumbnail doesn't do it justice
The video was just about SM64. I haven't seen the video creator before so I'm not sure if he does other games.
Some of it was a bit over my head but I think he implemented a 3d driver (?) that came later in n64's development which allowed for more polygons and stuff.
Either way, it was in no way an admonishment of the console! He's a fan demonstrating what the console was capable of, not dunking on how SM64 could have been better