COVID-19 Outbreak Information Updates (Reboot) [over 150.000,000 US cases (est.), 6,422,520 US hospitilizations, 1,148,691 US deaths.]

So was the school policy the root cause of the mental health issues or did it simply reveal the issue sooner rather than later?

For me its the latter. Those issues were there just hiding in plain sight while the world turned. Now, they are evident and can be addressed accordingly.

I dont think that several weeks ( or months in some cases ) of virtual school had an impact like you say unless those children were already predisposed to having some issues. For whatever reason.
I’m going to have to disagree with you. We can’t say “COVID didn’t cause morbidity and mortality…those obese, sick people were already predisposed to morbidity and mortality”. Even if isolation isn’t the ONLY factor, that doesn’t mean you can outright dismiss it as A factor.