Is multiple simultaneous speakers at the same volume/distance actually an important problem to solve? I already can't have a conversation if that's happening and my hearing is fine.
It’s a decently-common occurrence. There’s a significant amount of literature pointing to the fact that people who are DHH avoid group conversations because they can’t follow along (see references). This sort of falls hand-in-hand with speech localization, which is another unsolved problem (and likely is unsolvable without true AR).
https://journals.sagepub.com/doi/10.1177/1084713807301322