By then I will have a 4070/80Microsoft direct storage "preview" not available on windows until 2021 it seems. So games support it late in the year or 2022? Not quite the saviour then?
In the mean time worst case use DLSS or drop one setting on textures on the odd game that needs more than 10gb to work properly. Either that or sacrifice on 30% or more grunt, save £100 and go 3070 16gb.