Please refrain from spreading misinformation.
The report did not make that conclusion. It was a non-peer reviewed survey of 300 patients. Among other factors such as dining out, public transportation, social gatherings and the like, it asked the simple question on whether the patient had been wearing a mask the two weeks prior to testing positive. It did not follow up to determine if the respondents wore the mask properly (under the nose, on the chin, loose, etc). While the majority of respondents did say they had been wearing a mask, those who tested positive also where nearly twice as likely to have been in close proximity to someone who had already tested positive and/or had dined out at a restaurant where mask wearing is limited.
No conclusions were determined about the efficacy of community mask wearing from the study. Rather, those situations where the mask comes off such as dining out.
But... as has been pointed out on this board many times. YOUR mask only offers you minimal protection. Those infected wearing a mask dramatically lessens their ability to spread it. If both are wearing a mask the viral load is minimized to a point that helps slow community spread. There are plenty of peer reviewed studies that back this up.