I think you're basically right. I might phrase it differently: the connotation of "birdbrain" to negative intelligence isn't disproven by noting quick read and react capabilities to certain problems, as intelligence is about more than that.

Some birds have impressive specializations, and corvids clearly punch above their brain mass weight due to impressive efficiencies with their brain architecture, but I think the framing of the article is more wrong than right to frame it around speedy information processing of particular problems.