You thought OpenStreetMap data uses the WGS84 datum? No it doesn't
I get why OSM does this, and it’s not necessarily a bad thing. The most important thing is being transparent about what format the data is in and always including that information in the metadata. the article touches on this point in this blurb:<p><i>We should inform data consumers, so that they can decide to convert the coordinates to WGS84 if they want to.</i><p>As someone who works in the GIS space, if we get data without this crucial information it’s sometimes very difficult to find the original datum to perform transformations and usually amounts to some form of educated guesswork based on the warp from WGS84 and the origin of the data “what datum/projection would I have used if I was the data creator?”