I suspect that if this were a lesbian woman who had this happen to her the debate around whether or not the victim was in the wrong by any measure would be far different.
The victim was in the wrong, period. He was also murdered and the killer should be punished to the full extent of the law. Both of these things can be true and it's not needed to tell people how "accepting" you are by announcing how the victim did nothing wrong. Also, when you're confronted with being wrong, it's not useful nor is it a compelling argument to keep saying "That doesn't mean he had the right to kill him" even though literally zero people here have taken that position.