The tone of the last two lines, “was he free? was he happy? the question is absurd: had anything been wrong, we should certainly have heard,” is (in “the unknown citizen”)

The tone of the last two lines, “Was he free? Was he happy? The question is absurd: Had anything been wrong, we should certainly have heard,” is satirical.
This is probably because something really was wrong, and nobody heard anything about it. Satire is used to mock and ridicule people for their stupidity using humor, irony, or often exaggeration. This figure of speech is used quite often in literature.

It’s a hope that ; )