There's more to it than that. If you were describing Xanax rather than benzodiazepines as a whole then I'd agree with you.I'd pretty much agree 100%.
Not even just anxiety, but some people who find it hard to shut off after a long day. If you're already a pretty relaxed person, a mild dose of benzos, if anything, depending on your energy levels, will just make you feel sleepy. Though if you're unknowingly pent up with anxiety or can't shut off, a benzo gives you that calming relaxing feeling, which a lot of people find recreational.
Think you summed it up pretty well.
Xanax kills anxiety but I don't find it euphoric because it doesn't really do much else. It's bland and boring.
Diazepam and temazepam also kill anxiety but I find them highly euphoric. I think a lot of it comes from their muscle relaxant, sedative-hypnotic and anticonvulsant properties. It's not all about the mental 'I feel calm' aspect... that feeling of deep, profound physical relaxation is what really defines the experience for me. If you are a fan of GABAergics then you should enjoy Valium.