[acdha]

Those past changes were quite disruptive, causing malnutrition and death, wars, etc. The current rate of change is much faster so we should expect all of those to be worse because there are far more people alive now and neither humanity nor the ecosystem have much time to adapt.

[monero-xmr]

I disagree - I think modern society, international trade, and communication systems make such disasters far, far less likely.