Gorsuch is a textualist. This means he makes his decisions based on the plain meaning of the words used in statute and not the intent of the legislators who wrote the law.
The case turned on the meaning of "sex" in the 1964 Civil Rights Act.
Gorsuch wrote: “Only the written word is the law, and all persons are entitled to its benefit.” He concluded with “An employer who fires an individual for being homosexual or transgender fires that person for traits or actions it would not have questioned in members of a different sex.” And therefore, he said, the employer is in violation of the Civil Rights Act and the law.
I would not get my panties in a bunch if I were a conservative because his interpretation of the Civil Rights Act was in line with conservative constitutional interpretive principles despite what those on this board may think.
Conservatives will be praising him on his next decision I am sure.
Here is the full opinion for those that are interested: