not saying that the PS2 had no casual gamers, that would be silly. but the consumers that the PS2, Xbox, PS3, and Xbox 360 marketed themselves to were exactly the same- from the games, to the commercials, to the design of the console. heavily skewed towards males 14-35, who already have an interest in games. And judging by the total consoles sold at this point, their efforts were successful and this audience grew. "casual" gamers buying the ps1 or ps2 were still very likely males in that age group that still played games- just not as often. Casual gamers that bought the wii were just as likely to be 40 year old moms that never bought a console ever. Totally different comparison. the definition of "casual" gamer shifted wildly this time around.
There was growth in the GC to Wii audience, but nintendo targeted two totally different groups for both consoles, so looking at growth isn't all that useful.
Each generation, console makers have aimed slightly older. So, the third gen systems (NES and such) aimed at young children. The SNES and Genesis aimed at children and younger teenagers. The PS1 and N64 aimed at teenagers and children. The PS2, GC, and Xbox people in their mid 20s and below. Then last gen, 18-35 probably for the PS3/360, and all ages for Nintendo. People playing games keep gradually getting older, so the consoles adjust over time and keep aiming slightly older each generation. Each generation also continues to aim at the younger ages the previous ones did, though, so there's always more people being added at all age ranges.
(Computer games, by the way, have aimed at adults since the beginning, pretty much.)
So yeah, Nintendo did aim at a new market with the Wii, but Sony and MS didn't keep things exactly as they had the previous gen, either. And the Wii has a good number of traditional games for gamers; it's certainly not a system with only a casual base. The Wii was not just for people who don't play games at all, after all. I mean, sure, Nintendo did change their focus, but they tried to appeal to both groups at once.
Also, games like the SingStar line on the PS2 in Europe sold almost exclusively to what anyone would call a casual audience, and there that was a BIG seller. Quite a few of those "40 year old moms" bought PS2s for things like that. Many other people bough it just to be a DVD player and barely ever bought any games for it. You'd need to take that into account too.
But again, every generation sees a change in the gaming audience. That PS360 14-35 males target market you mention? First I'd say that by now it's really 18-35 that gets the biggest PS30 focus, but beyond that, yeah, the PS2/Xbox/GC were not aimed at that, not really. 13-25 for the PS2 and Xbox, maybe? As I said, audiences expand each generation. Nintendo did decide to expand it even more with the Wii, but they also released stuff for core gamers too.
It irritates me when people predict the end of consoles without making any suggestion as to what will replace them. Are they just gonna walk off into the sunset with a tip of their hat? Are Sony and Microsoft and Nintendo just going to say "adios guys!"? Why would you predict the next generation of consoles to sell over 200 million combined units then say they'll be the last?
In 5-7 years everybody will have fiber in their home and will ditch their consoles in favor of streaming services like OnLive of Gaikai, right? Only crazy diehards will actually care about owning anything anymore...
Now, for a long-term prediction that IS a possible (not good, but possible) future, but it's most certainly not one that's coming in the next 5 or 8 years. And while there is something of a diminishing of returns in graphics, that doesn't mean that people will say "that's enough, never buying another system now". That's silly, we're not at that point!
Now if the idea is that there's going to be a crash and that's why it'll be the last gen for a while... well, that's possible. But with those sales projections, Pachter isn't predicting that.