I remember a few from various stages of my life (born 1984).
Seeing the demo footage of Sonic 2 in Woolworths and thinking the leaves falling down in Aquatic Ruin zone was so cool and advanced.
The original Sega arcade of Virtua Racing with the moving cars completely blew me away.
I remember my uncle loading up Cannon Fodder on his Amiga, and a REAL song with REAL music came out, along with REAL photos. I was amazed haha.
A few years on I remember a PlayStation demo disc having promo footage of the first Gran Turismo and it looked so real to me, I watched it over and over. The first Driver on PS1 looked absolutely amazing to me also.
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.