It was nonsense. Other countries had long opened their schools by that point, and we had real-world models for making in-person school work. Schools in Europe had opened without masking, without social distancing and with no “infrastructure of testing.”
The Europeans put kids first, resting safe on (scientific) evidence that kids are at minuscule risk from the virus and spread it at a much lower rate than do adults. Weingarten was determined to put kids last.
In February, when the Centers for Disease Control and Prevention was finally going to issue guidance urging full reopening of in-person schooling, the AFT successfully lobbied for language that kept schools closed.
The next month, when the CDC finally did the sane thing and changed its social-distancing guideline for schools to 3 feet (from 6), Weingarten wrote a letter questioning the change and demanding yet more “safety” concessions.