Fair enough, I don't mean to discount the value of the metrics they did use. However I can think of two things that could be gained from testing people weekly.
1) If it actually prevents detectable infection altogether, it's some evidence of preventing spread, sooner. (as I understand we have some of that evidence now that it's in wide use)
2) If there are long term effects of even asymptomatic cases, we'd have some reason to believe that those are mitigated as well.
Just look at the hospitalization and death rates for old people in the countries with high vaccination rates.