The moral and legal responsibility of Government for K-12 children and college students are very different .
You can tell a middle class, intelligent 18 year old who has their own computer with good internet access and a safe home environment, to stay in their parents home and study on line and be reasonably safe in the knowledge that they will be ok.
A low Socio - economic 5 year old in an unstable home is in a very different situation. Providing them with in person schooling is unequivocally mandatory.
There is a difference between providing a luxury experience and a service of social need.