I will admit that I have hardly even seen the 'hero' type games, but that is out of principle - but what I did see was songs being watered down and treated like a joke, many of the notes you needed to 'press' had no resemblence on what was actually being played on the song.
I know that its 'fun' to pretend that you can actually play that stuff, even when you know full well that you can't - and I also understand that not everyone wants to spend years learning to play guitar so they can have that 'rock god' feeling, but its like a FPS player picking up a gun and running into a combat zone: they might think they know what they are doing, but in reality they know very little and will soon get cut to pieces.
The "rock god feeling without the hard work" is the main selling point with these games, but what happens to those people who want to actually play the real instrument? If they have experianced such heights of being a rock god in a video game and then a real guitar noob overnight I would imagine that alot of potential musicians will be put off by the actual effort they need to put in to play some of these songs for real.
Video games I understand are all 'make beleive' and 'lets pretend' that I am a space marine or a elf or something like that - but that is because they are NOT accessable. I know that in my life I will NEVER be an NFL superstar, or a space marine etc etc - thats why the games hold such appeal. Games like 'guitar hero' should be discouraged at best simply because the real thing is out there, easy to start and affordable. Hell you can't even say that its for disabled people because you need both hands to play the game as well as a real guitar! (well, more fingers help but even on bass you could live with 1 or 2
) The £100+ price tag on some of this shite you could buy real instruments for less, and if your worried about noise you could buy an electric guitar and plug it into a little amp with a headphone jack - simple!