That is not an accurate summary of the study. Emphasis mine:

> Limitation: Inconclusive results, missing data, variable adherence, patient-reported findings on home tests, no blinding, and no assessment of whether masks could decrease disease transmission from mask wearers to others.

> The recommendation to wear surgical masks to supplement other public health measures did not reduce the SARS-CoV-2 infection rate among wearers by more than 50% in a community with modest infection rates, some degree of social distancing, and uncommon general mask use. The data were compatible with lesser degrees of self-protection.

I don't think any public health experts are saying "wear a mask and you'll be safe", they're saying "if everybody wears a mask, that will slow the infection rate". A study of a community with "uncommon general mask use" does not dispute this.

Finally, I don't think it's clear that a randomized controlled trial is the best method to answer this question. Aside from ethical concerns, you can't give someone a placebo mask. Shouldn't we assume that people will behave differently when they're wearing a mask?

Here's the CDC:

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Data regarding the “real-world” effectiveness of community masking are limited to observational and epidemiological studies.

    * An investigation of a high-exposure event, in which 2 symptomatically ill hair stylists interacted for an average of 15 minutes with each of 139 clients during an 8-day period, found that none of the 67 clients who subsequently consented to an interview and testing developed infection. The stylists and all clients universally wore masks in the salon as required by local ordinance and company policy at the time.

    * In a study of 124 Beijing households with > 1 laboratory-confirmed case of SARS-CoV-2 infection, mask use by the index patient and family contacts before the index patient developed symptoms reduced secondary transmission within the households by 79%.

    * A retrospective case-control study from Thailand documented that, among more than 1,000 persons interviewed as part of contact tracing investigations, those who reported having always worn a mask during high-risk exposures experienced a greater than 70% reduced risk of acquiring infection compared with persons who did not wear masks under these circumstances.

    * A study of an outbreak aboard the USS Theodore Roosevelt, an environment notable for congregate living quarters and close working environments, found that use of face coverings on-board was associated with a 70% reduced risk.

    * Investigations involving infected passengers aboard flights longer than 10 hours strongly suggest that masking prevented in-flight transmissions, as demonstrated by the absence of infection developing in other passengers and crew in the 14 days following exposure.

Seven studies have confirmed the benefit of universal masking in community level analyses: in a unified hospital system, a German city, a U.S. state, a panel of 15 U.S. states and Washington, D.C. as well as both Canada and the U.S. nationally. Each analysis demonstrated that, following directives from organizational and political leadership for universal masking, new infections fell significantly. Two of these studies and an additional analysis of data from 200 countries that included the U.S. also demonstrated reductions in mortality. An economic analysis using U.S. data found that, given these effects, increasing universal masking by 15% could prevent the need for lockdowns and reduce associated losses of up to $1 trillion or about 5% of gross domestic product.

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Taken from: https://www.cdc.gov/coronavirus/2019-ncov/more/masking-scien...

No statistically significant protective effect for the wearer, but as the study points out, it says nothing about protection of those around the wearer, which is the commonly accepted reason for mask wearing.

For what it's worth, this doesn't mean anything (by this I mean that literally, you have gained zero bits of information from this result, and should be exactly as confident as you were before the study)

You are misrepresenting the results.

“ Although the difference observed was not statistically significant, the 95% CIs are compatible with a 46% reduction to a 23% increase in infection.”