The problem with this kind of "constructivism" (since the beginning of time) is that it is easy to neglect other factors that play a crucial role in the development of a crisis that may or may not be exclusive to each geographical region. For example, I've lived in Sweden and I've lived in London. The amount of differences (social, economic, political) that could be contributing to Covid-19 in one way or another is immense, and so obviously are their strategies. I would imagine the same applies for a country like Japan. Want another extreme example? Cyprus initiated a lockdown far earlier than London, and they have had 17 (0.0014% of the population) deaths so far. One can not and should not simply cherrypick situations and arguments to support one's case.

I wasn't asking rhetorically and am quite open to be proven wrong.

What kind of differences do you have in mind for Japan given their population of ~126 millions, density and median age?

"One can not and should not simply cherrypick situations and arguments to support one's case."

I don't think the fallacy of cherrypicking applies here. One counter example is enough to challenge a hypothesis and ask very serious questions about it. I gave two -- Japan and people staying at home and still getting infected in NY.

Do these counterexamples immediately disporve lockdowns effectiveness? I don't think so.

Do they mean some very strong evidence is necessary to confirm the effectiveness? In my opinion, absolutely.

"Cyprus initiated a lockdown far earlier than London, and they have had 17 (0.0014% of the population) deaths so far."

I'm going to give an absurd example but consistent with this line of reasoning.

So, I claim the Sun still rises thanks to lockdown, and as a result of initiating their lockdown earlier the Sun is brighter over Cyprus. So does the Sun still rise everyday? Yes. Is it brighter over Cyprus? Yes. Hence, my claim is proven!