Comment Re: Is it just that better students are skipping? (Score 2) 102
COVID-19 is a multi-organ disease that affects the brain as well (this has even been shown in MRI and histological studies). Many people suffer from brain fog, concentration difficulties and fatigue for a long period after the infection and there's no guarantee of a full recovery. Even though the brain of young people are more resilient, I'm pretty sure this plays at least some role in the drop of the results.
While you are correct in your description, the prevalence of PACS in the younger demographics would be insufficient for a notable change in test scores. Organ scarring detected by MRIs and histograms correlate to severity of disease, and would not impact the test-taking population in any meaningful way. The symptoms you describe are uncommon (especially in the below-49 crowd), and most of the individuals with those symptoms recovered 6-24 months after the acute phase.