Despite the definition, retrogaming appeared almost immediately after the emergence of the industry itself.
The heart of the developer: the Sega Saturn devs
Before the fifth generation, the hardware of consoles was about equal in performance and differed very little.
They still make new games for the 16-bit Sega Mega Dive
Quite recently I wrote about the release of an unusual long-build for the old Sega Mega Dive called Paprium.