Yeah I thought that was kind of an odd omission personally, though it does make sense. As you have to remember, there are all the options that the enemy can respond with, many of which are the same, and that alone was not something easy to do. However, player choice wise we will have on average 4-6 options for voicing lines per character, with more unlocked based on your tags (Hero/Villain/Elf/Dwarf/etc.), that's a ton of options.
I do hope we get a Divinity Original Sin 2 Enhanced Edition, with those lines voice acted, that would be a reasonable request, hopefully with an upgraded version of Polymorph so that we can turn into Were-creatures and whatnot, or the ability to do so gained through decisions and quests in game (i.e. become a Vampire, Werewolf, Undead / Lich, gain otherwise unique abilities or powers based purely on your decisions). I've encountered a few of these, though usually they are in the form of items. I've received a tag for being a Hero, and a special talent that gives me an advantage and a disadvantage (yet to see if it offers anything else).
