Nobody at EA Maxis questioned it when lead engineer Jamie Doornbos introduced same-sex relationships into The Sims prior to its launch in 2000, said lead AI programmer David Graham during a panel at EA's GaymerX conference.
The Sims was one of the earliest mainstream titles to feature same-sex relationships, which according to Graham is the result of Doornbos "just [doing] it, he just went in there and it was a thing one day."
The lead engineer "had more permission because it was seen as a kind of casual type game, so it would've been harder to have that happen in a huge AAA game," said Graham. Publisher EA also didn't believe the game would prove popular, allowing more forward-thinking features to be "snuck in."
"They didn't think The Sims was going to do well at all," said Graham. "They thought it was a terrible idea. So that was also a part of it: They thought, 'Who's even going to play this game?' And all that stuff kind of allowed it to sneak in."