Maybe that is not an accurate quotation in (or from) the Guardian. Elsewhere it is being reported:

Of Belgium’s registered deaths, 44 percent died in hospital (and were tested). The majority, 54 percent, died in a nursing home — and only in 7.8 percent of those cases was COVID-19 confirmed as the cause. (Yes, I know 44%+54% is less than a 100% - some deaths are in neither hospital nor care homes.)


Agreed, then, 54% are in nursing homes. But less than ten percent are confirmed to be because of covid-19, if those other reports are correct.

Everyone, including in these threads and the government spokesmen and their scientists, is saying international comparisons have to be done with extreme care because they do not all count the figures in the same way. Belgium is a very good example where the counting includes more than then UK system does.