To be honest how many "console generations" are even left?
By Playstation 5 I think you'll be getting to the point where relatively photorealistic graphics will be possible (at least to the extent that the general public cares about) that you're hitting the point of diminishing returns. Also likely is that the amount of publishers will be whittled down to maybe 5-6 big ones (like the Hollywood studios) because no one will be able to afford to make such high end games without a huge budget.
Beyond that I think what we consider high end chipsets now will become cheap commodities that can be cheaply integrated into cable boxes or the television itself, or into say a tablet or cell phone, which then can stream to a TV -- a lot of people simply won't need a giant brick under their TV to play games with relatively high levels of visual fidelity.
Not to mention I think streaming services like Sony's Gaikai will continue to improve and a "Netflix" equivalent to gaming is inevitable ... that'll be a situation where you really don't need a console at all, just a controller and a smart TV.
