I can’t really get myself that worked up over prescriptive grammar issues, but I do enjoy reading the arguments.
The adverb is an incoherent lexical category, a catchall. How are “there,” “yesterday,” “quite,” “assiduously,” and “indeed” all members of the same family? As we learn in school — in a definition that dates from Dionysius Thrax in the second century B.C. — adverbs modify verbs, adjectives, other adverbs, noun phrases, clauses, and whole sentences. Adverbs indicate place, time, manner, frequency, degree, certainty. Anything an adverb does can almost always be done more elegantly by the adverbial deployment of the other parts of speech. Almost always more elegantly: in most cases with more elegance. —Christian Lorentzen