I’m sorry, this seems a bit disconnected with the reality of actively working and simultaneously taking care of children. If you are working from home, there may be absolutely no or very little time to give quality instruction to children. Anecdotally, at the start of the pandemic, I was in a surgical residency. My specialty (otolaryngology) was locked down pretty hard across the nation, so I actually was at home a lot during the start of the pandemic, as there was a big scare about risk with routine ENT encounters and surgery. My wife worked in HR and was totally working from home.
For the first two months, I did most of the child care despite being in a busy surgical residency. Our children were about a year old and required a lot of active watching and caring for them. My wife may have been able to step away and change diapers and feed (sometimes she would be tied up). There was certainly no time to give quality education.
To give quality rearing and education to children while working would essentially be the equivalent of working two jobs. Working from home does not necessarily mean you log on, sit at home, and then go about your day as you like (i know some may have been able to do that, for better or worse). I’m not sure why you are insisting that parents taking on this extra burden while working (from home or not) is an unreasonable explanation for this.
I’m sure the overall reason is stochastic, with other concurrent contributing factors, but writing off what is generally considered to be the main reason for an acute change in educational metrics (which coincides pretty spot on with am abrupt interruption in home life and school life) doesnt seem reasonable. I haven’t heard anything besides the pandemic, being the main driving force for the acute change in educational metrics. Raising a child and reading to them is different than directed education. I value the time I have with my children and read to them daily. This is very different (but complimentary to) than what they would get at some sort of structured pre-k.
This is one of those situations if your looking at the “why,” you have to use judgment. All of the data is of course, retrospective, which is not as good as a prospective stuff such as a randomized controlled trial (which it would, of course be unethical to perform). When thinking about stuff like this, I like to point people out to a peer-reviewed systematic review that shows parachute is not associated with survival when jumping out of airplanes (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC300808/). The point is, we can’t always clinically study some thing in the best possible way because it’s either impractical or unethical, and sometimes you just have to use your best judgement unless/until something more concrete comes to light. We cannot, ethically, do an experiment where we recreate many of the conditions at the start of the pandemic and to conduct an RCT that this drastically affect education (including early education and development).
That being said, I do agree that we should do what we can as parents to raise them, read, help educate, teach good life skills and help instill positive personality traits. I do agree that screen time, distractions, and overall pace of life have been a contributing factor to this for many years, and no-doubt, have played a role at least in the background during this acute decline.