A lot of great innovative things occurred for gaming in gen 8 (a lot of bad stuff too). 4K HDR. Battle royale shooters. Hero shooters. Dolby Atmos. Gaming as a service/on demand.
But the one thing that will stick with me is Nintendo perfected console quality gaming at home and on the go. I'm still amazed that I can play Breath of the Wild in my media room plus on the go at the airport with little to no quality compromise.