As such I guess 'area" rather than polygon was originally decided upon for good reason?
As they say, the road to you-know-where is paved with good intentions. :-) The canonical essay on those "good reasons" is the annoying Terminology in GIS topic in the Release 8 manual, which, mercifully, was edited out of the Release 9 manual. That essay was originally written years ago, around Release 4.50, when Manifold's main interest was making GIS more accessible to ordinary people.
That essay's thesis is still valid, that if you want to make GIS more accessible to millions of ordinary people it is better to use common words like "line" and "area" and "drawing" instead of confusing words like "arc", "polygon" and "coverage". But the essay could have been much less overbearing when pointing out the mathematical illiteracy of Esri's use of those terms.
Since then, both Esri and Manifold have lightened up. Esri now uses "lines" and Manifold recognizes the inertia that has built up from decades of Esri terminology. There is still a deep interest in making GIS accessible to "ordinary people", but that has to be wrapped around what has emerged as a higher priority of making more powerful GIS that can work effectively and pleasantly with ever-larger data.
Here in the Manifold community people have become accustomed the word "area", so that sounds natural to us. But if you go to a gathering of people who use other GIS packages, all you hear is "polygon."
For translations, "area" works in English because it is one of those words that has many meanings, and often just the right meaning, in different contexts. That effect also works in other languages, but it's not true of all languages. It's like the English expression "OK," which can mean both "yes" in answer to a question and "apply" in the context of having made an option change, and similar when used as a label on a dialog button. Not all languages have such a universal expression that can mean "yes", "accept", "apply", "commit" and so on, with just one tag applicable in different contexts. I think that's why many languages just leave it as "OK", a new word they've imported from English.
It's not simple to change "area" because the word is used in Manifold code and documentation to mean "areal measurement", "region" and "area object" so you can't just do a search and replace. Somebody who understands the context of its use has to go through every instance in the code and in tags (knowing when a tag is used as a caption for "areal measurement" as opposed to "area object") and also documentation. With around 14,000 illustrations, over a thousand topics and millions of lines of code, that can take a while. But it's doable, probably only around a man-week.
That's not worthwhile for our community, but I go back and forth on whether I think it's worthwhile to make Manifold more accessible for people in the Esri, Q, and spatial database communities. I've seen a few simulations and they read quite naturally, although it's weird how for the first few moments you feel like you're reading some Esri documentation. :-) For example:
Drawings are made up of points, lines, and polygons. The drawing seen above has buildings drawn using polygons, footpaths and roads drawn using lines, and individual locations of interest drawn using points. The points, lines, and polygons in the drawing have been Styled using varying colors and symbology, for example, blue star symbols for the points.
After a few paragraphs like the above I find myself forgetting that "area" was ever used, which is another weird feeling when you catch yourself in that remembrance. But then, I read a lot of non-Manifold GIS stuff so I'm very used to "polygon".
I keep getting the feeling that sooner or later it would be wise for Manifold to listen to some of the larger organizations that are pushing for the change. They have their well-established ways of referring to things and they don't want what is for them is an alien word. For our community, I don't think it would be a wrenching change, since in our community people are used to hearing both words. But definitely it is something to ask about, to hear how people feel.