We’re very specialized kinds of mathematicians, sometimes. In other languages the term is often “Information Science” and in German, IIRC, it’s “Infomathics”, both arguably better names.
Theoretical Computer Scientists write mathematical proofs showing the limits of how information can be stored, transmitted, permuted, hidden, and extracted. Practicing Computer Scientist learn the current best ways to do the above and write implementations thereof. Examples:
Storage: Compression algorithms like zip files, jpeg, mp3
Transmitted: protocols like FTP, HTTP, and yes, ActivityPub
Permuted: A lot of sound editing is done by turning an array of of pitches over time into an array of frequencies over time, changing those frequencies, then turning them back.
Hidden: Encryption, obviously, but also steganography
Extracted: Decryption, obviously, but also natural speech processing and image recognition


Depends on if you think of formal proofs as a kind of code, I guess.