Maybe it's in the details? The article reads as if it was longer known that astrocytes somehow modulate neurons, but not the mechanism behind it, not what exactly there is modulated and on which stimuli.

I imagine it's the difference between knowing that a layer inside an ANN "processes information" and knowing the specific semantics that this layer represents.

Researchers also know that astrocytes are active participants in computation for some areas that have been studied (vision and also memory).

The article seems about 5 to 10 years late.