I agree the formula is simplistic.
Reading U is interesting. They had to close their new campus in Southern Malaysia very early on, in line with both Malaysia, and nearby Singapore's prompt response to Covid 19. Both countries appear to have a "good pandemic", at least so far, and the campus will be reopening for the new academic year.
If I were a SE Asian student looking to study in the UK, I might ditch my KCL place and, depending on the options to later transfer to the UK, opt for starting in Johore Baru.
So yes the University, like all businesses, might appear to be stretched if they made major investments just before lock down, but in this case it might prove a sound decision.
Ditto SGUL. I suspect they have virtually no assets. Their teaching is delivered in a hospital presumably using hospital facilities, so don't need the sort of buffer the article is looking for. They have strong demand for their courses, so as long as revenue is greater than costs, they should should be at no more risk than they were before lockdown - and indeed less than many as they don't have a large dependence on overseas students, and some of their staffing will be in the form of Clinical Teaching Fellows etc who will essentially be borrowed from the hospital, as opposed to more standard Universities with tenured staff.