That might be so, but the word "Abyss" does have a meaning - bottomless chasm, and does make associations with something. The word "Baator", as far as I know, doesn't.The names Baator/Baatezu and Tanar'ri were most likely made up of whole cloth during second edition, when TSR pretty frantically tried to remove anything "demonic-looking" for a while due to religious panic.