I agree with that last kid, Kershaw should have started the ASG.
It certainly could have gone either way. I think Kershaw's classy endorsement of Harvey was a big factor. That along with the game being played at Citi Field and Harvey being the exciting new kid on the block with all the hype just made for the perfect storm. Kershaw's been doing it for a lot longer now, even though he's actually only a year older than Harvey, and unfortunately that makes him somewhat boring to a lot of fickle fans.
And Harvey does (and did at the time) have a higher WAR than Kershaw.