Sorry OP completely disagree re secondary schools
1-childcare
Whilst you can leave secondary kids at home alone, some are only 10/11yrs old, it’s not easy to say they will be fine, many parents wouldn’t be comfortable with this.
2- home learning
It’s far easier to have a parent/ guardian help a primary school child count etc. My nephew was only year 7 during lockdown but he had Spanish, IT coding, music composition to learn, no way could my sister or bro in law help with those. These are kids heading towards life deciding examinations, they can’t just crack on at home.
3- facility access- even if you give them all
Laptops it’s far harder to ensure a teenager actively logs in and does the work required.
4- mental health. Teenagers are prone to depression, lots of hormones and changes. I would say they suffer more from isolation than younger children, you cannot cut them off from their peers.
Combined with the safeguarding issues/ lack of a free meal for some- a terrible idea. Close everything before you close schools!