I think there's still value in "whom", but I also acknowledge that grammar, like spelling and word use, is a tense, messy blend of prescriptive and descriptive. As "whom" falls out of verbal use, and as written language becomes more reflective of spoken, the rules of what is acceptable change (and, as the article notes, the rules of what comes across as pompous and pedantic change as well, hastening the process).
Life, and language, goes on.
For Whom the Bell Tolls
The inexorable decline of America’s least favorite pronoun
To whom it may concern: Next you will be telling me I can no longer use the word “whilst.” To what is this world coming?
They can take my “whilst” away from me when they it pry it from my cold, dead words.