Yes, we have video-games and games tags. The wiki for the former describes when it is appropriate to ask a question about a sci-fi (or fantasy) video game:
For questions about the plot or backstory of a game with science-fiction/fantasy elements. Questions about playing the game or the mechanics are off-topic here, but may be on topic at Arqade (https://gaming.stackexchange.com/). Game identification questions are also on topic as long as they're specifically about a Science Fiction and Fantasy game.