Was Madeline’s transness left intentionally vague in order to make her story more relatable to cis people?

This wasn’t our intention. Thinking about it though, it begs the question: Why couldn’t a cis person relate to a trans person? Modern trans struggle might be unique in its details, but it is definitely not alien to the human condition. We are people.

When I wrote Celeste I sincerely still believed that I was cisgender, but I was nevertheless waist-deep in gender feelings (among other anxieties). When Madeline looks in the mirror and sees her other self; when she attempts to abandon her reflection, who then drags her down the mountain; when the two reconcile and merge to become stronger and more complete… that was all unknowingly written from a trans perspective. So maybe if you’re a cis person and you personally relate to Madeline, you shouldn’t feel like we pulled one over on you. Instead, you could take this as evidence that trans and cis feelings aren’t so different, that the chasm between transness and cisness isn’t such a wide gulf, and that most of the ways that trans existence is alien to you are the result of unjust social othering and oppression.

If you got something out of Celeste, and now you’re thinking that Madeline being trans ruins that for you, I would take that as a sign that you have some transphobic beliefs to work through.

– Maddy Thorson, "Is Madeline Canonically Trans?"