Edit: Why the downvotes?
They have this long long outstanding bug where if they deem the audio low-quality (despite the fact it's crystal clear) they gain the audio and it goes crackly and too loud. If you turn down the volume... they gain it again, and again, and again, till you need to restart the app. Only for it to happen again.
The challenges related to audio sucking are mostly individual end users' audio stepping on itself, such as feedback from speakerphone configurations into its own microphone. Easily solved by good quality bluetooth headsets, wired headsets, or simply using something as basic as holding an android or ios phone up to your ear.
And I do put "video quality is consistently good" in the category of "makes peoples' lives slightly more convenient". It's not essential.
Tone, emotion, and intent are incapable of being conveyed properly without facial expressions and audible cues.
<rant> We are supposed to be engineers here. I regularly see this attitude that one thing is always and inherently better than another. Life is (mostly) a zero sum game and it is our job to pick a solution for the problem at hand. And the more we can constrain that problem, the better, cheaper, more reliably we can deliver a solution. More information is not better. Maybe for interview body language is important but for deciding what story to pull or what commits you did? Not really.
</rant>
If you're one of the few people that don't have person-to-person interaction on a daily basis - congratulations. However, that places you firmly in the minority.
I think you've missed the point completely. It's not a question of convenient UI. It's the reliability of the video call. I've tried numerous video conferencing tools, and the differentiating factor is literally just whether or not the video quality is consistently good, whether the call is dropped or not, and whether the audio is audible.