In a trailer for the first episode, Radcliffe can be seen listening to the trans and nonbinary youth discuss their identities and their hopes for respect. 

“There are some people in the world who are just not trying to engage in this conversation in any good faith,” Radcliffe says in the trailer. “I think a lot of the time it’s just because people don’t know a young trans person so there’s just this, like, theoretical idea about this in their head.”

This isn’t the first time that Radcliffe, who has been a supporter of the Trevor Project since 2009, has stood up for trans rights. In June 2020, the actor responded, via a statement released through the Trevor Project, to comments Rowling had made on Twitter about transgender women.

“Transgender women are women,” he said. “Any statement to the contrary erases the identity and dignity of transgender people and goes against all advice given by professional health care associations who have far more expertise on this subject matter than either Jo or I.”

A day earlier, Rowling had sparked controversy by publicly expressing through a series of tweets some of her most anti-trans comments to that point

In his statement, Radcliffe said his comments should not be taken as “in-fighting” between him and Rowling, adding she was “unquestionably responsible for the course” of his life.

But he said he felt “compelled” as a supporter of the Trevor Project and as a “human being” to speak out.

“To all the people who now feel that their experience of the books has been tarnished or diminished, I am deeply sorry for the pain these comments have caused you,” he added. “I really hope that you don’t entirely lose what was valuable in these stories to you.”

Source: https://www.buzzfeed.com/davidmack/daniel-radcliffe-trevor-project-transgender-youth-roundtable