These articles are like comparing weather and climate, things can get lucky for a year or two just like we can have a winter freeze and the hottest summer on record back to back. Short term changes should be considered in context with long term trends. Just because one can be contradictory from another doesn't mean there's a malicious agenda or someone is lying, just that the world is a big enough place that two things could be happening at once. The GBR stretches for a really long way, just like the weather isn't the same in California as it is in Washington doesn't mean that there can't be patches that are doing okay when the conditions turn for a few years, but compared to how the reef was 50-100-1000 years ago *shrugs*
Crown of thorns are exclusive coral eaters, I dunno what doc you watched
@Lambianz but they do not eat snails, snail and snail relatives are more likely to eat them and maybe that's where it got mixed up? To my knowledge there isn't a consensus on the exact cause of the recent proliferation of crown of thorns but most hypotheses do point to something relating to humans (removal of key predators, nutrient run off, etc)