How can I create a visualization from data in Unity?

Currently, I’m creating a city simulation game, and I’ve run into a problem that I have no idea on how to solve. How can you color in parts of a map from data? Similar to how all SimCities handle visualization.

Technically, I could spawn one gameobject per each point, and then color it in, but that would mean creating about 10,000 gameobjects, which is simply not an option.

You could plot the data with D3.js and then use SVGAssets from the store to import it as an asset. Alternatively you could simply create a bitmap plot and use that as an image but the SVG route might be more versatile from a data viz point of view.