It depends on how the voxels relate to the gameplay.

Regardless of the original intent, in Minecraft the voxel grid itself is a very important aspect of the core gameplay loop. Smoothing the voxel visual representation disguises the boundaries between individual logical voxels and makes certain gameplay elements more difficult or frustrating for the player. When the visuals closely (or exactly) match the underlying voxel grid, it's easy for the player to see which specific voxel is holding back some lava or if they're standing on the voxel they're about to break.

In Minecraft you can, for example, clearly count how many voxels wide something is from a distance, because the voxels are visually obvious.

In Red Faction, you're never concerned with placing or breaking very specific voxels in very specific locations, so it's not an issue.

So your point is, Minecraft uses voxels on a unit scale. Red faction uses voxels differently, so Minecraft wins?

I get the appeal of Minecraft but Notch didn’t invent this stuff as much as you would love to believe. He simply used it in a way that made it easy to understand. To the point where people like you are explaining it to me like I have never played it. I have. I was one of the first testers.

Almost all of Minecraft is ripped off other games. World creation, dwarf fortress. Mining, dig dug. The only original thing was The Creeper.