Ceterizine does cross the BBB to some extent, just less so than a lot of furst gen ones. So it can still have some hypnotic effects, sure.
But that's not the important difference here. The important difference is that ceterizine has negligible antimuscarinic effects, unlike DPH, meclizine, cyclizine et al. Antimuscarinics are nasty drugs, and the antimuscarinic activity(and sometimes other non-histaminergic activity as well) is why a lot of first generation antihistamines are so bad for your brain.
But that's not the important difference here. The important difference is that ceterizine has negligible antimuscarinic effects, unlike DPH, meclizine, cyclizine et al. Antimuscarinics are nasty drugs, and the antimuscarinic activity(and sometimes other non-histaminergic activity as well) is why a lot of first generation antihistamines are so bad for your brain.