Where can I find research that confirms masks work?
"The authors of this article, published in 2015, have written a response to their work in light of the COVID-19 pandemic. We urge our readers to consider the response when reading the article. https://bmjopen.bmj.com/content/5/4/e006577.responses#covid-..."
Would not standard practice be to wear proper masks?
Yes, here we go: "some subjects in the control arm wore surgical masks." And indeed, someone comments "The control arm had less than 1% of no mask use".
Surgical masks are widely available and not solely for healthcare workers.
Which is only sorta true in the sense that people who are sick often wear them and they're not almost unheard of like in the West. But pre-pandemic, go out on a crowded street in Tokyo and you probably wouldn't see more than a few masks if you saw any.
But even with the confirmed cases the trend in Japan is worrying, especially compared to other countries in Asia. They're setting new records every day: https://www3.nhk.or.jp/nhkworld/en/news/20201201_36/
With that said, I absolutely think the mask culture in Japan has dampened the surge a lot. In countries without this people just do the bare minimum to be compliant, so we have all these chin-wearers and nose-flashers. We're simply hopeless at wearing masks even with the strictest of mask mandates. So even if masks could reduce the spread significantly we're not likely to see the effect of that here.