The graphs date back to 1985. The font is small though, so it's easy to misread.

> it also seems inarguable the ecosystem has become highly unstable as well over the past 20 years

That's extremely arguable! Extrapolating from a tiny number of data points is how AIMS managed to screw up previously. There's really very little data on which to build predictions about long term trends. We have no idea how stable or unstable coral sizes are because it's just not been monitored for long enough to say. We're zoomed in to a tiny, tiny part of the coral's history, which is far longer than humanities own.