I'm not sure if they were already there before beta 3 for WotR. I been using the animation speed and it really works great. I only completed BG3 EA once (before druid announcement) but i already completed WotR beta twice and looking forward to the 3rd playthrough.
I think perhaps it's a trade off? Larian made those animations to be longer and make every actions to be more impactful? As such i think it will have more longer animations compared to a basic attack like WotR. I'm not sure how Larian can further reduce their animation time. But to add more party members, they have to perhaps solve the animation time IMO.