The actress filmed two episodes for the planned series before bosses at the streaming service shared the shock announcement that the show was not moving forward.
Speaking on SiriusXM's "The Jess Cagle Show", Hilary opens up on the cancellation, insisting officials at the company are "really trying to figure out what kind of content they want living on Disney+."
"And that doesn't totally align with, like, where I see Lizzie right now," Hilary says. "I'm very protective of her and they're very protective of her."
The actress and the show's original creator Terri Minsky wanted to take the revived series in a more adult direction to match the age Lizzie would be now - but Disney chiefs didn't have the same vision.
"The one thing for me was just the way that she could connect with what was going on in people that were watching the show," she reflects. "And so, for me, it only makes sense to me to shoot a show where she's acting like a 30-year-old in a modern world."
"There (were) a lot of creative discussions where maybe they were thinking that's not quite right, and we were trying to make it work," Hilary adds. "And, you know, there's always, like, lots of conversations, but I don't think it's going to be happening."
However, Hilary is remaining positive, sharing, "It was lovely to relive that even for three weeks of my life, because, you know, there was a point in my life where I couldn't stand Lizzie McGuire."
"And I was like, 'I don't want to hear that name ever again.' And now that I'm my age, I'm, like, I love her. She's, you know, this is where it all began for me. And she is me and I am her. And I brought what I could to that, which was very much just who I am inside. And so to tap into that again, even for a moment, was really a great experience."