Which SciFi ttrpg has the largest player base?

[Jason]

*cough* Doc Smith *cough* Asimov *cough*

But even Lensmen or Foundation, or Starship Troopers or Dune or Ringworld or Neuromancer, they're all great books, but none of them are really the Lord of the Rings of science fiction. For whatever reason there is no equivalent. Nothing quite so obviously dominant in its influence on everything that came after it.

Star Wars is the equivalent for science fiction film, but it didn't affect sci-fi literature nearly as much.