I disagree. If a character on screen is to the side of the screen, audio should project from the appropriate front side or front side in addition to the center speaker, not just the center speaker so it sounds as if it's coming straight down the middle. Maybe it's not an issue if your screen takes up 5 degrees. However, when your field of view obviously shows two characters 40 degrees apart but sounding as if they're both standing on top of each other, something's wrong.
Positional audio can be so bad on 5.1 I can pick out which speaker is being used quite easily because the game doesn't seem to mix speaker use for the same audio source. Devs seem content with shoving most data through the center channel and using everything else for environment.
Before developers work on better aural clarity and range, I'd much rather they work on positioning. I should be able to sit in the middle of a multichannel setup, close my eyes, and point out direction and distance for every distinct audio source.
Some games are quite annoying when there's multiple characters, some with their backs turned or facing a different side, and the only way to figure out who was talking is to look for a moving mouth or read subtitles. Suspension of disbelief breaks easily if you're character is moving and the noise source off to the side only changes volume as you approach and pass and doesn't change speakers.
As a side note, some movies are terrible at this. You can have five or six characters in the scene, the camera angle may move around, but lo and behold, all conversation flows from the center channel only. Movies like that actually sound better downmixed to stereo to make everything equally defective.