Populous was a blockbuster game and it predates both Warcraft and Diablo by half a decade (released 1989), so it is indeed a striking omission. It's also the first game I can remember that used the concept by that name.

yes, but a lot of other games of the era also used the concept. It is not significant.

Sure, but it did little to bring the word to modern-day gamers compared to the impact that WoW and other RPGs has had.

It did, indirectly as a whole generation of developers has been exposed to it... And they made the games you know today.