Probably Tom Hall. The breaking point for him was Doom; When you look at the level of interactivity/story in Doom 3, consider that it was 'closer' to his vision for the original than what was released in 1993.

Anachronox is probably the best example of what he thought was a 'proper' game, and while I've never had the chance to play it, I understand it was a very underappreciated gem in it's day.