The perceived increase in "graphics" has certainly slowed over time. Some people may not have been gamers during the SNES -> N64 days, which is a leap the likes of which the world may never witness again.
But just because it's slowed down doesn't mean that it can't still be appreciated, even today. New, impactful, graphical technologies are always in the works, and I can't wait to see how things look in 5 or 10 years.