The doctor told them they would need to start hormone therapy and have surgery to insert prosthetic testicles so they would "look and feel like a normal man".

[5][6][7] They have since become outspoken about ending unnecessary cosmetic surgeries performed on children with atypical genitals who are not old enough to give informed consent.

[8] Gallo attended the New York University, where they trained in the Experimental Theatre Wing at the Tisch School of the Arts.

[3] The crime thriller follows the young intersex sex worker named Ponyboi, who works at a laundromat with his pregnant best friend Angel (Victoria Pedretti).

[3][6] The film was positively reviewed in The Hollywood Reporter, which wrote that Gallo's screenplay "achieves something still rare in an industry unnecessarily confused about inclusion: Ponyboi seamlessly integrates its character's challenges with identity into a propulsive story about a sex worker on the run.

[20] Gallo was profiled along with Alicia Roth Weigel and Sean Saifa Wall in a documentary about intersex people called Every Body, which premiered at the Tribeca Film Festival in 2023.

[21][22] In 2019, Gallo won the GLAAD Rising Star Grant, which they said they planned to use to mentor LGBTQIA+ students in Los Angeles public schools.

[6] They have supported California Senate Bill 201, which would ban doctors from performing cosmetic surgeries on children with atypical genitals until they are old enough to give informed consent.