Back when I was a sprout and leveling SCH in Heavensward before dungeon content got HP-nerfed, I did stone vigil. Tank kept dying, I got blamed. The actual reason? Tanks gear was broken.

Moral of the story: People like to blame healers for their own shortcomings or the faults of someone else. Just ignore people like them and can just blacklist them after (even if you're not likely to see them again any day soon or at all).