His comment is factually correct and has nothing to do with CPU usage for stuff like net code, AI, etc.That bold part would tell me you've never developed a game before...especially one that needs lightening fast online code such as in a fighter.
A fighting game, especially one on a single plane effectively is VERY graphics lite an can be controlled much easier in terms of its poly throughput. You can pull off a ton of tricks like no LOD, low res textures, and a fixed size arena that's essentially a diorama.
Agree with him completely. Fighting games are easier to code visually, AND need to be, because frame drops would be ENTIRELY unacceptable to almost every single buyer of said game.