The creator of the Cyberpunk 2077 VR mod CD Projekt recently hit with a DMCA strike has paused his Patreon page and pulled access to all his mods after receiving another strike from a different publisher.
Looks like the Ghostrunner developers also have an issue with paid mods running off their IP.
I mean to say, there’s no T&C with retro games.
There can be, but most of the time yes.
And it depends on the definition of retro games. Retro games can include up to WiiU and Xbox360 era, there is a lot of T&C there.
But for the good old 8/16bit era, yes it is mostly unkown there.