Calamities feature heavily in RPGs: if you’re going to have an epic adventure, better make the stakes big, right?
In the ‘murder-hobo’ mode of adventuring, it could be argued that the adventuring party is the calamity: monsters are just going about their business, getting by in their various ways, and then this party shows up and starts indiscriminately killing everyone. Especially if the adventure features tribes of sentients (like goblins and orcs), this has gotten a (deservedly) bad aftertaste of colonialism and racism. (POCGamer has a good overview of colonialism in D&D.)
There is another mode of adventuring, where the party is part of established society, but a group of evil-doers are preparing to overthrow the status quo in some kind of calamitous way, and (often) going about this in a ruthless, haphazardly way. This means that the characters are not the movers and shakers in the setting: they are merely reacting to what the ‘evil’ group is doing. One could argue that the group are the actual protagonists, and the party are simply antagonists that try to prevent something from happening. It’s interesting to see that almost all ‘evil’ groups are indeed, actively evil and ruthless, casting the adventuring party as the agents of good and reason. I’ve hardly ever seen a scenario where the group scheming to overthrow the status quo are actually trying to make things better for everyone — overthrowing an oppressive regime, for instance.
And then there are the natural disasters. Mostly these happened in the past, and serve to explain why a town or castle is abandoned — often as a prelude for the ‘monstrous’ species to make their home there, before the adventuring party goes in and kills ’em all… I don’t think I’ve ever seen a natural calamity occur ‘in-game’. Would it be fun to play a group of adventurers trying to evacuate a bunch of people out of a village, in time before the volcano erupts? There might be a Ryuutama scenario in there somewhere, with some hard choices as to what you can take with you and what you have to leave behind to become prey to the lava…