Personally, I too am also annoyed with all these "Retro" games. The reason being, it's so pointless to reproduce such a game on a modern system.
Pointless? Why? There's nothing pointless about people programming games they like on a platform that's got a much wider audience than a retro console that has a small fan base, complete with people like you who are complaining about it not being on an old platform instead.
Sure, if I had a Pentium+ with 2GB of ram, I could churn out anything of 8-bit quality with a touch of innovation/cool factor. But that's no real feat or amazing achievement.
As was stated already, go ahead and do it then. You make it sound like it's so easy to program games just because the machine is newer. Programming games is not simply about performing great feats or doing something that's to be considered an amazing achievement. Producing a fun game of good quality is the most important factor. Feats/Achievement dickwaving come secondary, if they come at all.
Not that I would play it on a modern console, but I have way more respect for games like "Retro City Rampage" which at least started running on real 8-bit hardware. That's much more impressive/purchase worthy than some random PC game made to look retro.
You "8-bit purist" types all sound like idiots when you say shit like this. You're spitting on people's effort and work just because it's not on an old machine which makes it clear that you've sort of missed the point of independently made games.
Some people who pour a lot of effort into a game would like it to be enjoyed by a wider audience, complete with people who actually appreciate the time/effort that goes into making a game.