I don’t know how anybody could quantify that or ascribe it to one TV show.
obviously it’s not a single TV Show, there are many; and it’s the cultural acceptance which has rapidly propelled this change.
like I said, I have never seen the show, but when my best friend’s son came out as gay, her daughter who was in medical school at the time, commented how they were just like so and so on Family Guy. That’s why that line or reasoning resonated with me, I had heard it cited, personally.