I politely disagree with your premise. I dislike video calls and have never found them technically clunky or unreliable.
Slack Webex Teams Zoom Skype
Of those, Slack and Teams both cut out at seemingly random times. The others, though, were generally reliable.
If you feel like it’s wasting your time you are probably in a meeting you shouldn’t be in or it’s not properly organized with specific goals that need to be addressed in the meeting.
I feel like running an audio stream in the background and just do other things is not something that solves that. And why wouldn’t you be able to just minimize the video and do what you want to do if you don’t feel like attending?