Yes, absolutely. But it'll pass Wii thanks to being supported for longer and by more publishers, not because it's a cultural phenomenon that's growing the market.
Actually, thinking about it, from a global perspective it is growing the market, and expanding console gaming into countries that have never really been interested in it before.
Now, sure, the more mature western and Japanese markets are showing a shift away from dedicated gaming devises and onto Smartphones, but I'd say that's less a market shrinkage, so much as it's the natural shift in gaming that new, more appealing hardware has brought.
Those millions of super casual, non hobbyists that bought the PS2, Wii and DS haven't gone away, they're if anything gaming more than ever, it's just that there's a more ideal device they're buying instead of dedicated gaming hardware now.
Meanwhile the number of people buying a games systems because they love gaming seems to be rising.
The increased software sales, high attach rates, rise of indies, resurgence of PC, success of the gaming focused Switch and PS4, all show positive growth in pretty much all markets.
Compared to the relative failures of casual focused, underpowered WiiU and the anti consumer, 'Kinect, TV and Sports' marketed XO at launch (it's ongoing failure to establish its own identity, especially through first party output also hasn't helped), these are clear examples of a rejection of what many saw as the direction the market was headed in last gen.
So basically I see Wii (and DS and PS2) not as a cultural phenomenon and high point for the market that can never be achieved again, but simply a wider shift in society sweeping up those who weren't being truly catered for by console gaming, driven by the steady worldwide acceptance and embracing of gaming as a hobby, that naturally crashed on the rocks of Mobile once the technology they never knew they really wanted became commonplace.
PS4 may infact be the first games system to reach 100m in sales almost entirely off the back of an audience who genuinely love gaming and aren't just after a cheap DVD player, lifestyle accessory player, or disposable distraction for long journeys, at least since the PS1, and even then I'd say PS1 was the beginning of the influx of non traditional console gamers that have thrown all our data for measuring success completely out for decades now.