The actor also reveals which pivotal season 4 scene wasn't originally included in the script.
The 17-year-old actor addresses his character's sexuality and season four arc, confirming that it's "100 percent clear" that Will is gay and in love with his best friend, Mike (Finn Wolfhard).
"Obviously it was hinted at in season one: It was always kind of there, but you never really knew, is it just him growing up slower than his friends? Now that he's gotten older, they made it a very real, obvious thing," the actor tells Variety in a new Q&A.
"Now it is 100 percent clear that he is gay and he does love Mike. But before, it was a slow arc. I think it is done so beautifully, because it's so easy to make a character just, like, all of a sudden be gay," he continues, noting that he has been approached by numerous fans who have related to and are moved by his performance.
"That just made me so happy to hear," he says. "They are writing this real character and this real journey and real struggle, and they're doing it so well."
That includes, he says, showrunners the Duffer Brothers writing new scenes on the fly. In one standout moment from the fourth season of Stranger Things, Will's big brother Jonathan (Charlie Heaton) opens up a heartfelt line of communication with his sibling. Through a conversation about their childhood, Jonathan hints that, yes, he's aware Will is gay, and he wants to be there for him.
"This scene was actually not originally written in the script," Schnapp reveals. "It was only until after I did the scene of my in the van, where they saw me crying and the protectiveness that you see with Jonathan looking in the rearview mirror. They were like, we need a scene with that. So they wrote it as we were filming.
"It's also very important for people to see that Will is not alone," he continues. "Because all we ever see of him is struggling and feeling depressed and that he can't be himself. Jonathan is talking to him in code -- it's just the perfect way to tell someone like Will that he cares about him and he accepts him no matter what. I think it was really wholesome."
The van scene to which Scnapp is referring has been made into a wildly popular social media meme, which the actor admits he has seen "everywhere."
"Honestly, it feels really good to get that recognition for that scene," he says. "Just that little turn told you so much. Everything was done so intentionally, like when I put my hand over my mouth. He’s hiding it, and he doesn’t want Mike to hear him. It’s just really cool that people loved it."
Schnapp says he's "super unserious on social media and pretty goofy," explaining away his recent TikTok misstep of sharing a private direct message from GRAMMY winner Doja Cat. The moment exploded across the internet, with the singer slamming him for his transgression. Since then, Schnapp has said the two are "all good" and that he apologized directly.
"I posted that not thinking too much of it, but obviously it hurt her feelings," he tells Variety. "So, as I should, I apologized and she was totally OK with it, and it was like, 'I'm sorry how I reacted.' It was all good. I love her. I'm like the biggest fan of her music and I told her that. I was like, 'You're literally my role model.
"It's all good," he continues. "People make such a big deal out of everything when it's on the internet, but, like, in reality, it's like a two-minute thing."
As we wait to find out what will unfold in the fifth and final season of Stranger Things ("Obviously, we hope for a coming out scene," Schnapp says), the actor is dipping a toe in the entrepreneurial pool by launching his own vegan hazelnut spread, TBH.
"I’ve always been super interested in entrepreneurship. It’s always been something I’ve wanted to tackle and be a part of and build a business," he explains. "I was just brainstorming all of my passions and what I care about, what I love, and I just kind of combined my favorite things. I love Nutella. It’s my favorite thing ever, but it’s so bad for you and so bad for the planet. And so I was like, there’s a gap in the market for that. I need to fix it."