If anything, core games will continue to sell, it's a matter of marketing and how the video game characters and gameplay be perceived by the public.
As for this graphics, I think it's suffering from diminishing marginal returns when it comes to impressing the crowd.
The graphic jump from the NES to SNES was considerably large, so is the jump to 3D from the SNES to the N64. GCN produced much more realistic graphics, but starting from this gen, the new graphics on the consoles didn't look that much more impressive compared to the previous transitions. In fact, if graphics are the only things to focus on, the consumers will find it harder and harder to make out the difference and wonder if anything's changed at all. Especially since it takes a very careful look to see how much detail a game has these days.
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