How about exposure to actual coronavirus? Most everyone is exposed at least to small degrees on a daily/weekly basis given the levels in air.
Because if no covid/vaccine is showing a much higher or similar delta as covid/*, that would be pretty worrisome. I think that seems to be missing in the given study.
“In participants that had COVID-19 and were tested one week after symptoms developed, antibody tests detected only 27% to 41% of infections. In week 2 after first symptoms, 64% to 79% of infections were detected, rising to 78% to 88% in week 3. Tests that specifically detected IgG or IgM antibodies were the most accurate and, when testing people from 21 days after first symptoms, they detected 93% of people with COVID-19. Tests gave false positive results for 1% of those without COVID-19.”
https://www.cochrane.org/CD013652/INFECTN_what-diagnostic-ac...
Sitting at home and working all day is really bad for your health, especially if you do it on/off for two years.
The group in question - 25-44 year olds - are primary members of the workforce, and most likely saw their work shift to WFH for extended periods of time. Anecdotally, all the people who worked from home within my circle struggled a lot with inactivity and weight gain, coupled with poor diets.