The mini Sega Genesis is real: The Sega MegaDrive Mini
https://www.cnet.com/news/sega-megadrive-mini-announce/
First, there was the NES Classic. Then the SNES Classic. And now, the Sega Genesis is making a miniature comeback too.
Behold, the Sega MegaDrive Mini, just announced in Japan to commemorate the system's 30th anniversary. (MegaDrive was the original name for the Genesis, in case you didn't know.)