Masks helped keep Japan's COVID-19 death toll low, says expert panel. https://www.japantimes.co.jp/news/2020/05/28/national/science-health/masks-helped-fight-coronavirus/ …
The trajectory from late March to the first week of April or so was very alarming, and there was for real strain on the medical system, as well as widespread fear of collapse. It was very hard to get a covid test in Japan before they loosened the rules in late April.