Yes they're starving but without a natural predator to them then they will just rebound if kelp grows back. The article did mention that the starfish predator

Yes they're starving but without a natural predator to them then they will just rebound if kelp grows back. The article did mention that the starfish predator of the urchin died from a mystery disease. I wonder if that starfish was reintroduced into the area if it would be able to survive again or simply die from the disease again. I think the key to fixing this issue is to figure out the reason the starfish died of the disease. Then it might be possible to mitigate for that.