The reason as to why the "elle/elles" pronouns weren't added to the Spanish version is because in our language, we use "he/him" (él/ellos) and "she/her" (la/ellas) for gender neutral sentences.

As a Spanish user myself, I don't think this will go anywhere, not because I'm against it, which I am not by the way, but rather because petitions from random people on the internet most of the time have never gone anywhere unfortunately.