For once, I disagree, though I agree there's an issue.

The issue is with the meeting. There is no point in being at a meeting where you have so little to do that coding is a better idea.

Meetings should be short, fast, and have exactly the right number of people you need. If you discover you need someone else's input, stop the meeting and schedule another one, or if it's a rush, rope them in for a few moments and then send them back to work.

Keeping cameras on makes most people more comfortable. I don't love being on camera but I always turn it on, because I can hear a bit more stress in people's voices when I don't.

It should be each worker's preference - many people are even less happy on camera than I am! - but I would personally advise anyone who asked to keep the camera on, and simply leave the meeting if you aren't needed.