128 kbps audio sounds fine and video quality is much less important than audio. A typical video call uses 720p video at 30 fps, which Twitch says you can stream at 3 Mbps (and pro streamers probably care more about quality than most people do). I basically wouldn’t worry about bandwidth unless you use a physical whiteboard or otherwise need really good video quality.
Re: overall bandwidth
128 kbps audio sounds fine and video quality is much less important than audio. A typical video call uses 720p video at 30 fps, which Twitch says you can stream at 3 Mbps (and pro streamers probably care more about quality than most people do). I basically wouldn’t worry about bandwidth unless you use a physical whiteboard or otherwise need really good video quality.