There us an old saying, attributed to Mark Twain: "There are lies, damned lies, and statistics." The graph above entitled "Mask Usage vs Daily Positive Cases" is a great example of a case where statistics are worse than a "damned lie".
Not that I don't believe the numbers. I have no reason to doubt them. All good statistics are simply factual numbers. So how do statistics become worse than damned lies? In their interpretation. Justin Hart completely ignores the fact that while mask use stayed relatively constant while the number of daily cases rose and fell, there were other factors that could have had an affect on the spread of COVID. The summer surge came as states started reopening because of COVID, and this huge winter surge that we had was predicted ahead of time, as experts warned that large holiday gatherings would cause a huge uptick in the number of cases. If Mr. Hart had data comparing mask wearers versus non-mask wearers performing similar functions we might have something for which we could determinethe usefulness of masks. But the chart he showed is completely worthless.