You're drawing a very simple conclusion from quite a complex article though. Some of the things it is noting: * School closures during the Covid-19 pandemic we

You're drawing a very simple conclusion from quite a complex article though. Some of the things it is noting: * School closures during the Covid-19 pandemic were one factor behind the unprecedented decrease across the OECD. * The general decline also began before the pandemic. * Immigration was quite probably a factor. Even without getting in to the details.