This is one reason the ruins can feel more prosperous than the final generations actually were.

The climate story also needs a time scale.

A society can tolerate a gradual environmental shift if it has time to adapt.

The danger comes when several difficult years arrive close together or when a long-term trend reduces the margin of safety.

A hay harvest does not have to fail completely to matter.

If it becomes slightly smaller every year, farmers may gradually reduce cattle numbers, change herd composition, or rely more heavily on hunting.

Those decisions can preserve survival while quietly changing the economy.