Well, if COVID 19 already spread through the majority of the population, neither intervention will have any affect. And there's a very good chance that is did, over the winter-
Could CDC Data Prove COVID-19 Infections in November 2019? - UncoverDC
That's a bold claim. We won't know the answer to how many people have had the illness until an antibody test is available.
The estimates from Wuhan are that 81% do only experience a mild illness so this could have been responsible for the uptick in influenza like illness seen in late stages of 2019 in the US. However about 15% experience more serious illness and 5% experience critical illness and half of these die. So where was the uptick in critical illness patients and deaths if that article is correct that it has already burned through the US population. It only talked about an increase in reports of influenza like illness. If people had reported to ICU with severe difficulty breathing and required ventilation and a chest x-ray revealed widespread lung inflammation, the doctors would have recognised and reported it as something different to flu. They did not do this, so either all the doctors in the US are stupid or negligent or both.
Seriously, if you really believe that COVID 19 is **more** infectious than the flu, why would you believe it's juuuuust now showing up in places like the United States, which is at the end of the flu season? How can it simultaneously be more infectious, and incredibly slow to spread?
It is more infectious. For every person with the flu they infect something like 1.4 - 1.6 other people via aerosol transmission. Covid-19 infects about 2.2 people. I don't just believe it, it is what the evidence demonstrates.