There are so many issues with it. Our schools tried it.
Here's the issue we encountered.
Child must be supervised by an adult - this is difficult when you've 5 children.
One child per room in household - having 2 main rooms in my house, they weren't happy for us to use bedrooms.
No other disturbances in the room, so if in kitchen someone can't use the electricals or be in the background. This is also why they want one child per room.
Internet speed - everyone using it, slows it down, resulting in lagging and dropped connections.
Each child needs a phone, tablet, any pc, this isn't possible with 5 kids.
Changing the picture onscreen, I've seen mine put fake deer ears and horns on heads and faces.
Everyone talking over each other, it starts out fine but with lags someone gets cut off, someone isn't heard, there is always one person doing all the talking and it's never the teacher.
Teachers that teach more than one subject have more work to do.
Swapping between teachers for different subjects always caused connection issues.
Getting a suitable time for everyone was a nightmare, fine if you have one child or even 2. But anymore it becomes ridiculous.