[2023] Can anno go back to being on one map please?

I understand the sentiment, but can already tell you that it's unlikely to happen.

One point is performance: You can only make one map so large until the impact on performance gets so big that it becomes a problem. Having multiple regions helps. Alternatively, we'd be rather restricted in terms of map-size.

Second point are region-specific mechanics: It allows us to create different behaviours and different mechanics for different regions (e.g. freezing in the Artic) much more easily by assigning them to specific regions.

Thirdly, also, the "I'm in a different place now" feeling is easier to get across when it's actual regions.