My instinctive feeling is that extensive testing works well at the beginning of an outbreak when you're looking at a few hundred/a thousand cases, but if you miss that window of opportunity then testing is best used in a highly targeted way unless you can easily do vast numbers of tests.
Yes, we missed the point in the ‘containment’ phase where we could’ve followed South Korea’s plan. I don’t mean that as a criticism, really, just an observation. East Asian countries have had prior experience with a less-contagious still-serious Coronavirus, SARS. Lessons learned 15 years ago will have greatly informed the responses of countries in the region.
Looking at the UK’s pre CV19 ‘HCID’ documents, it seems to me that our government (successive governments, not just present day) have never truly believed we’d ever end up in this position. They planned for handfuls of ‘imported’ cases of new infectious diseases, but not for a disease that had already begun it’s ‘community spread’.
Whether that’s due to naivety, a kind of systemic xenophobia or simply that our governments think almost exclusively in 5 year plans, I don’t know. It doesn’t make much difference at this point in time anyway.