Well, if it's copy and pasting professors of thermodynamics explaining
how radiation transfers in both directions between two bodies, why don't you explain where they go wrong?
With a vacuum gap in between the source of heat and the passive block,
radiation transfers heat from the heat source to the passive block and the block rises in temperature to that of the heat source.
Although many factors affect short - term trends (and some longer - term), the current rise in temperatures can not be explained by those other factors and it is entirely consistent with the known physics of CO2 and
radiation transfer.
In this case you have the diffusion transfer equation, which similarly has a differential of hot and cold terms describing the heat flow, as does
the radiation transfer equation, and we all understand that heat does not physically diffuse from cold to hot and that physical contact between a cold object and warm object does not make the warmer object warmer still.
However, the solution for
the radiation transfer alone is unrealistically sensitive to the GHG concentration, due to the omission of convective, sensible, and latent heat transfer.