This article looks at three different cases by the Supreme Court, two already decided and an upcoming decision, that have the potential to remake or undo the "administrative state", as conservatives like to call it.
Effectively, the Supreme Court is mandating that Congress legislate only in the way it authorizes.
The gross mischaracterization seems…neither that gross nor mischaracterized. The magnitude of difference between you explanation and the first quote doesn't seem that big to me. Then again, I'm also not a lawyer.
In any case, I don't think this substantially addresses the article's argument. I'll concede that you're right. There's still the concerted effort to undermine the Chevron doctrine, however characterized, which grants more power to the judicial branch.
To me, this statement sounds like the Chevron doctrine prevents courts from ruling on whether particular policies of administrative agencies conform to the law.