"The line “Hell is other people” in French reads “L'enfer, c'est les autres” or “Hell is [the] others.”
(The best known English translation of the play, by Paul Bowles, actually renders the line “Hell is just – other people.”)
We get a little more of the flavor of the line in English if we read it as “Hell is the Other"
https://rickontheater.blogspot.com/2010/07/most-famous-thing....
In English, we are okay with "the young" and "the old" but shy away from doing the same with other terms, especially in the plural. "The poors," "the gays," "the olds" are all considered derogatory trolling.
Not so in French. The best translation of "les autres" really is "other people."
Another example of this is the film ‘Au revoir les enfants’ which a literal translation would render as ‘Goodbye the children’ but is really just ‘Goodbye children’.