Tynan dug himself thaf hole. An article outlined emergent story telling in Rimworld and how it manifests from code. It wasn't defamatory, it was quite matter-of-fact and the sort of example you'd use in a game design course to demonstrate how a game can imply something in its mechanics, intended or not. The article even went out of its way to pre-emptively defend Tynan, saying that it's almost certainly the result of placeholder values sue to be an unfinished and unbalanced game.
Instead of seeing the article for what it was, which was mostly lauding the game, Tynan got defensive and instead of leaving it be he started making foolish statements. He started going on about how there's no such thing as a straight or gay woman, that all women are actually bisexual, and that there's no such thing as a bisexual man. In the LGBT community we call that lesbian erasure and bi erasure. The first being the idea that any self-proclaimed lesbian just needs a good dicking from a straight dude. That idea leads to a lot of sexual harassment and is even the basis for corrective rape. As for the bi erasure, it's the notion that somebody's sexual orientation is defined by who they're currently boning. That notion is the basis for the brand of gay conversion "therapy" that originated in the United States and has since been exported to most of the world.
Now I'm not going to call Tynan some atrocious bigot because I don't think he is. He was clearly feeling attacked when he said those things. His statements were very ignorant though and it isn't hard to see where people get the idea that he's bigoted from. It's all about how much you're Tynan when he says that he isn't. Given that violent homophobia is extremely common it isn't hard to understand why people weren't willing to give him the benefit of the doubt. Tynan made very poor statements that never needed to be made and people made reasonable conclusions based on those statements. He dug that hole all by himself.