Barry was billed as the guy who was going to heal the Earth and lower the oceans. He stood at the podium soaking-up accolades (and a Nobel Peace Prize) on issues he hadn't and couldn't even address.
Of course he should take the blame for sitting on his ass in the gulf. To be fair no one can magically fix it but if you're going to run as the messiah, don't act surprised when people get pissed because you can't perform miracles.