The Importance of Being Earnest, by Oscar Wilde
I think one of the writers who gets most overlooked in this type of regard, while not a modern one, is Oscar Wilde. Though he wrote in the 1800's his work is incredibly modern and stands the test of time better than nearly everything out there. I think his best work is "The Importance of Being Earnest". Talk about examining class privilege and sexism in an era where the very idea seemed almost mad. Not to mention the fact the Wilde is funny as hell, even today. "Earnest" is so well-crafted that it contains laugh-worthy lines in rapid succession, but sustains this frenetic pace for an unthinkable amount of time.
Not to mention the fact that Wilde was a prominent author who was viciously persecuted once his sexuality was discovered. He might be one of the best comedic writers of all time, and he's so darn good that it can overshadow his social criticism or muffle it, because even those staunchly opposed to him can't help but laugh at his cunning wordplay.
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