You cannot seem well-educated if you aren’t at least a decent writer. How’s that for a bold proclamation? Go ahead, get offended. Disagree with me. Challenge me. That’s all good and well. Will you be able to adequately argue your perspective to me though? Because that too will depend on your skill as a writer.
You can be a creative genius, a math wiz—plenty of other things, sure. I didn’t say that you couldn’t be a genius. But in a world where even casual conversation takes place in large part over text message or email, you will sound quite ignorant indeed if you can’t keep your grammar and punctuation in its right place.
You need not have brilliant metaphors nor creative rhetoric running through you—not all of us can be Ernest Hemmingway and Kurt Vonnegut. You just need to be able to send a written correspondence or express your opinion using your words.