"Since some people take sense 2 to be the opposite of sense 1, it has been frequently criticized as a misuse. Instead, the use is pure hyperbole intended to gain emphasis, but it often appears in contexts where no additional emphasis is necessary." [1]
Thank you for looking that up and providing the reference. The M-W argument is flawed when the bit that "literally" modifies already is hyperbole. "Abuse of language sends me through the roof" is hyperbole. "Abuse of language literally sends me through the roof" is just ridiculous.