Good point. There has been a lot learned about how to care for COVID patients, not using a full mask to provide oxygen for example, that improves the survivorship. The falling COVID death rate, may be similar to the declining murder rate in the 90's. It wasn't that gun violence declined, just that survivorship from the shooting pandemic improved, due to improved medical interventions.
https://www.reuters.com/article/us-usa-newyork-crime/even-as-shootings-rise-murder-rate-falls-in-new-york-city-idUSKBN0EL27520140610