You're making the same argument as the post, it's worth reading. He is saying that telling people they can't use "literally" as an exaggeration is wrong becaus

You're making the same argument as the post, it's worth reading. He is saying that telling people they can't use "literally" as an exaggeration is wrong because words mean what you want them to. He is also explaining that the dictionaries that have updated "literally" to show this usage are not dictating anything, they merely reflect the way the word is being commonly used.