Yes, the target demographic is far more important than how much or how little color there is.

SO is an M-rated shooter in a market with plenty of them already, and it's main hook is being "meta" in a way that few outside the core audience would appreciate. And whatever pedigree Insominac had to sell the game based on the studio involved was built on Sony platforms; this is only the second game they've had on an MS box, and I doubt Fuse left a good impression. The color palette was the least of it's problems.

I havent played much Halo, but its sucess created the conditions for that kind of envyronment on the Xbox systems.

Err... i'm gonna have to disagree. Neither one of those games are developed by Nintendo.

Look at Splatoon to see what they do with shooters.

Well you know, if it's creative or colorful it's not going to sell minus a few IP's, mainly Nintendo ones

Sunset Overdrive sold very well. Especially when you consider Digital downloads arent tallied. Not to mention that doesnt factor in the bundle sales either. Im sure MS is very happy when it comes to that front.

I'm saying there may be people turned off to Sunset Overdrive simply because of presentation. It seems these day an M rated game with a presentation like that struggles to achieve great success.

Most people who are going to play Sunset Overdrive don't even know about Fuse. According to VGChartz, SO has already sold more than Fuse's combined sales.

A bad game doesn't turn a studio into a pariah especially if they have a good track record. Fuse wasn't the worst shooter I ever played... just really boring.

Nope, many adults like colors. I'm nearly forty and I'm thrilled about the look of Zelda U they showed for instance. World of Warcraft also sells to a lot of adults.

Maybe. But it good not bad marketing and can we really say that what Watchdogs had as better marketing accounts for more than 3 times the sales?

Everyone has biases (and mostly a lot of them) and these are usually influenced by media/family/friends. So yes, we are brainwashed. If people don't believe that, they should start reading lesswrong: http://lesswrong.com/top/

That's exactly what Insomniac did when they turned Overstrike into Fuse, and it bombed. 

That I would disagree with. Nintendo-games usually are above average, meaning that more games are worse than better than Nintendo-games. If you would say 'some games on non-Nintendo consoles are better than most Nintendo games', that would be something to agree with. But as every platform has a lot of shovelware the claim as you made it is definitely wrong.

EDIT: Also to comment towards your claim of average age of gamers as 33 (based on what study, which games are included - smartphones games often have an adult audience), some simple questions to ask are: what is the median age and how many of the gamers are kids. Because you see, an average can be misleading. In the case of ages - no one can be below 0 years old and mostly very small kids can do activities like gaming at all. As an example: if game A is played by 10 ten-year-olds and 5 eighty-year-olds the average age of the gamers is 33, but that doesn't mean the game is played mostly by adults.