Elite students from lower socioeconomic strata will likely be harmed. Elite students from upper strata will probably pull farther away (though may or may not suffer as compared to the counterfactual non-pandemic case).
To use your model, what you say is possible, but I think it's equally possible that the delta is additive rather than multiplicative. A 20% student and a 100% student might both lose 10% or 20% to [10%, 90%] or [0%, 80%] without intervention by involved parents.
My kids (grade 4 and 6) are getting a ton of dedicated 1:1 time including more coding time, paid math programs they enjoy playing, white-boarding problems with us, watching Nova/Nasa/other science content with us, and a lot more reading than if they were chained to a desk learning 2 hours of material in 6.5 hours. They might do better in this half school, half home school situation.
To use your model, what you say is possible, but I think it's equally possible that the delta is additive rather than multiplicative. A 20% student and a 100% student might both lose 10% or 20% to [10%, 90%] or [0%, 80%] without intervention by involved parents.
My kids (grade 4 and 6) are getting a ton of dedicated 1:1 time including more coding time, paid math programs they enjoy playing, white-boarding problems with us, watching Nova/Nasa/other science content with us, and a lot more reading than if they were chained to a desk learning 2 hours of material in 6.5 hours. They might do better in this half school, half home school situation.