Agree, forcing them to stay indoors is jus awful in so many ways. DH had to quarantine after seeing a client in France after we took DS to uni. He stayed in the spare room and didn't go out but it was awful. And we discussed the going out thing - if he went out for a walk or cycle and didn't go near anyone else how could that be a problem?
The rules are ridiculously rigid. If our sick DCs went out for fresh air, and to keep their muscles moving, but don't go near anyone else why is that a bad thing?
What amazes me is how resilient and cheerful they have been (mostly, and I do know it's a huge struggle for some, and I do sympathise).
It's getting harder and harder to support authority now. For me at least.