Boomer take, but going from NES to the SNES and seeing the advances in sprites and animations in Nintendo games like Donkey Kong Country, Link to the Past, Yoshi’s Island, and Super Metroid was really mind blowing.
Also seeing the early days of more cinematic approaches to storytelling in SquareSoft games like FF IV, VI, and Chrono Trigger. Those really forshadowed how games would mature into a serious storytelling medium for me. FF IV’s opening scene on the airship and the music is still burned into my brain.
The transition to 3D the following generation was also insanely impressive obviously, but none of those games have aged half as well as the 32 bit era.