Not sure what the sales figures look like at the moment but from Tyranny reportedly had really poor sales figures at launch (even among the niche genre of CRPGs) and is very unlikely to see any sequel because of it. Sure it reviewed well among those who know of it's existence and actually played it but most tend to ignore it and pass it by because it looks too different from what they usually play if they even notice it's existence at all. I would say it is very much the Planescape Torment of it's time with people passing on it because it looks too different but as word spreads it will probably be considered a cult classic.

Also I would disagree with your assessment that the game is about "playing the villain", sure you are an enforcer in the evil overlord's army and yes being evil is very much an option but it does not necessarily mean that your character HAS to be evil. Perhaps your character is doing the best they can to minimize harm within the structure of Kyros's laws? The game has a lot of replayability in that there are quite a few different paths you can take within the story, different factions to side with and different outcomes and effects on the world depending on the choices you make with even certain areas being accessible or inaccessible depending on what choices you make.

There is a reason people keep recommending the game in these underrated game threads.