@Megadude: While reading this topic, i see your problem that lead into the rant in the OP.
You are making false assumptions about when a game is released, it's automatically going to sell millions. The problem with this kind of thinking is:
1. History shows the opposite.
2. In order for a game to sell well, it has to be good.
3. It has to have appeal outside the plain gameplay due to competition.
Your whole "defensive argument" is based on a conversation that goes this:
A: "OMG game X sold Y amount of copies. What a flop!"
B: "I don't think it was even expected to sell more than that."
A: "Look at how much better game W did."
B: "It's a better game with broader appeal."
A: "No. The game is 1st party and i don't like it. 3rd party games don't sell. Look how much better game N did on PS360."
B: "It did, but the type of games tend to sell well on the HD consoles. This game was the type of game that we rarely see being made. If they would sell better, we'd be seeing more of them. Besides, look at how game G did on Wii."
A: "But that game was a sequel in established franchise, new original IP:s don't sell. Look at game C, it did so good on the HD ones."
B: "It did. But game F is new and original IP and it did at least as good."
A: "1st party games don't count. New and original 3rd party IP:s don't sell on Wii."
B: "Yes they do. We have atleast a dozen original 3rd party games that did very well."
A: "But the one original 3rd party game on HD consoles did so much better."
B: "Surely these games did well, after all, they're already planning a sequel. I don't think it would be getting a sequel if it had flopped."
A: "They should be selling more on an installbase that large."
B: "There's more competition on the platform."
Etc. Etc.
Basically what happened was the original claim started as an offensive. Someone replied it with reason, and the first guy started to make his own standards that every game should have fit in, in order for a game to be successful in his books.
Now, in your OP, you're either trying to create your own standards on the subject, or just (trying to) mix up explanation and excuse.
If a game doesn't sell, i don't think it needs excuses, since by default games aren't going to sell in huge numbers, but offering explanation to sales numbers (whether they are high or low), based on things that can be observed is fair. The type of conversation you're whining about stops when people start to accept the sales numbers and stop whining "i don't like game A selling so badly in relation to game B". Just look at PS2, best selling home console ever and the vast majority of games did badly, even by the standards that make Wii games to sell badly. And why is Rols joke thread the only thread the only one that points out how badly PS360 games do.
As for the people who have played games longer than the last two gens; people who got into games during SNES, NES or earlier are more likely going to find Wii the best system available, since Wii is taking the step back to what was important in games back then: fun. The "greatest game in existance" is always going to be inferior to "funnest game in existance" for the reason that people tend to value the latter more.
@Tuoyo: I haven't played any AC game, so i cannot say about them, but i thought Let's Go to the City was complained about being too similar to the GC title, not the DS one.
Disaster was really good. Only gripes i have, is the inconsistent graphical level and that the game should have been longer (although, it does have a lot new things to do on the second round). But, i can understand people not liking the game, since games that mix different genres tend to split opinions.