Yes, in rare cases of idiopathic insomnia antihistamines and other types of cns depressants may not work, but a benzo should very rarely be the first choice when trying to treat it. (Various stages of mania may be exceptions, and generally only short term until any underlying issues are addressed)
From personal experience, in periods of high stress and other things going wrong, nothing but benzos could reliably allow me to choose to fall asleep. Short term (for me it was just a few times a month) I’m sure the side effects were harmless. A handful of other things simply did not work.
Having a strong lever to push my sleep schedule back towards healthy even when I had, say, taken a five hour afternoon nap, was extremely useful.
Being given other things that not only didn’t make me fall asleep but let me lethargic most of the rest of the next day… and having to wait months while doctors experimented with “safer” things was extremely frustrated and led to worse effects than were feared from avoiding benzos.
