But I think that people tend to fall back on tried and tested rather than come up with new types of specialist classes for RPGs.
And even when they don´t they still kind of do. When playing MUD:s at the dawn of the internets, it was fairly common to start out as a commoner or civilian, and would then as soon as posible select your occupation, mage, thief or warrior, as it would usaly be better to specialize then to be good at nothing.
I think it is kind of hard to get away from, the link you posted(nice read btw) even listed pokemon.
I think in the end fantasy worlds are a good way to create your own scenario while the player stilll needs little information to get it. The worlds in the Final Fantasy game are realy twisted but as a player you kind of accept it as, okej, the system works like this.
Also even though the mage warrior thief system sounds kinda boring i tend to like games that has a clear class/job system better. Every character in FF12 was just the same while in 9 I had to choose: I want the good fighter to suck up damage but also i want the healer but then i cant have the good summoner = fun