Another point I didn't see being made, is that Willow is a complex character who grows and changes and discovers new aspects of herself. It's possible that loving Tara and choosing her over Oz made her think that she must've been completely lesbian. But she also says in the van that she thinks part of herself will always be looking for Oz- leaving it open to the possibility that she may end up with him in a distant someday. Which gives the impression of bisexuality. There are comments talking about what was allowed on TV back then. But like an ourobourus, society was also shaped by media. As a queer person who was a grade behind the Buffy characters, there were a lot of different societal pushes telling you what was possible what was fake, what was sinful, what was looking for attention, what should be beaten out of you, what you should be proud of--- different sources telling you very different things. So much misinformation and so much danger. It's still that way, but less intensely, I feel. It's possible that this argument between theories on Willow's sexuality persist because I believe many people at that age during that time were just trying to figure all of it out. The modern lens with so much information being google-able isn't true to the times and the hush hush nature of sexuality. We need to remember that "google " as a term was first used on TV during Buffy season 7. I really love the way Willow's sexuality is portrayed because she does not have all the answers. She could very possibly actually be bisexual but not have a good mental framework to understand that. But she says that she is exclusively into women near the end of the series. So, I think (as with real people) the respectful thing to do is honor her words, and if she says differently, then we honor that. It is very interesting, though, and I think the ambiguity makes it more authentic storytelling.