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While I agree that the 8th generation will be smaller than the 7th generation, I don't fully agree with the reasons or the overall impact.
I will be shocked if the combined Wii U/One/PS4 total passes 200 million and surprised if it passes 180 million but 150 million is a tad pessimistic though.
The reason I think it will shrink is two-fold; one being that the majority of the transitional audience the Wii had has gone over to different forms of gaming and the other being a shorter hardware cycle due to increased focus on features and extras and social integration plus the ever accelerating overall technology advancement.
I also believe, again due to these factors and the added notion that the One and PS4 are even more similar than the PS3/360 ever was in almost all regards, that all the consoles will have a flatter sales curve than the ones of the 7th gen (certainly none of them will repeat the amazing straight up and straight down curve of the Wii).
Will the 8th gen fail though? I suppose it depends on your defintion. Financially for the console manufacturers? Hard to say at this point, I'm leaning towards an overall yes though. Fail to expand the market; yes, without a doubt, most of the Wii's expanse was temporary and the console market as defined by core console gamers and software didn't really grow that much at all.
I'm not sure if this is anything but a semantic debate in the end, there are all sorts of failure.
For instance, as far as I'm concerned, the 8th gen is going to be a failure for me for continuing on the path set by the 7th gen in design philosophy and online/social focus since that's not my cup of tea, that hardly qualifies as an overall, objective, failure though.
Anyways, interesting subject!
Edit; OP, didn't you make a similar post a few weeks ago? This one is more thought provoking and less extreme and actually holds some merit, in my opinion. Something along the lines of "the future does not have your console in it" or something like that.
