The biggest problem with education is trying to make a horse drink water - the horses that don't feel like drinking at the moment monopolize the resources of everyone and dictate the techniques used. Everyone is led by the teacher in a ritualistic dance at the end of which, if the dance steps are followed, mastery is supposedly achieved. Those who can be engaged by this kind of thing and dance along with the class do well. Those who don't care to dance are unteachable - labeled dumb.
When first introduced, compulsory education was compulsory because the compulsion was necessary to force parents to give up the labor of their children so they could be educated. Education was an opportunity, and there were few who would not compel their children to take part if they could afford it.
Today child labor laws and the general way society is configured make children worthless as labor. Time in school is if anything is the financial equivalent of 'free babysitting'.
After a certain age it's impossible to keep someone in school and learning if they don't want to be there and the level of compulsory education should therefore be low anyway. K-6 makes more sense to be compulsory than beyond.
The idea that there should be a diploma at the end of it all and that that diploma should 'mean something' undermines the value of that diploma. By insisting that it certify a minimum standard, we guarantee that the standard is very low. If graduation rate is a priority than that priority is at odds with not only the level of the standard, but the possible level anyone can achieve. Catering to students who don't want to learn deprives everyone else. Dragging people kicking and bucking into education sets people against anything to do with it. The process of having education shoved down one's throat even turns people who would otherwise be receptive to education off to it.
What would be better would be for a certain number of years of education be paid for, and students can go as far as they want. They don't get a diploma, they get a transcript. They learn basic skills, not because they must, but because they are prerequisites to a class they are interested in taking. They want to pass for lots of reasons, such as peer pressure not to be the oldest kid taking the class, but also because they want to take some other class. If someone is behind in some area they can concentrate their efforts there.
Grades aren't important. Make classes pass/fail but keep the standard for passing high enough that students who pass have demonstrated enough understanding to succeed at the next level. Students who excel would have a broader transcript, or complete the courses offered early. But there is no need to penalize someone who struggles in a certain area if they have demonstrated mastery eventually. If they have truly mastered whatever it is, then they should be as able as anyone else who has mastered it to apply it in the future.
Can older, engaged kids benefit from well produced virtual classes? Sure. Will fourth graders watch the screen intently enough to learn Long Division? Will a 'tech' necessarily be able to answer a frustrated student's questions in a helpful way? If they can, then they aren't too bad at teaching... Couldn't they conceivably do as well as the video teacher? Yep, better probably. And does the video get paused every time one of the kidnergarteners has a question? Does it then become impossible to engage with?
That's one of the problems with the ritual dance method of teaching. Everyone brings certain things to the table before the class. It's hard not to fall asleep and miss the stuff you need to hear, or waste your energy doing useless ( for you ) dance steps and be too tired from that to learn anything difficult. It's better to be engaged in learning and spend your time on the stuff you don't know. When people do this they apply the sharpest edge to their problems and tend to cut through difficulty like a laser.
School should make that possible.