I think your confusion is the other side of what the article was discussing.

The problem is, there have been a lot of number systems in the past. The one we currently use is based on the Arabic system. In common usage you would simply call them numbers. But in a technical sense, to distinguish from other numbering systems past and present, they're also called Arabic Numerals because that's their origin.

Clearly this ignores the fact Arabic is still around and using real Arabic numbers and that is both confusing and maybe problematic. But I think the technical reason it sticks around is to acknowledge their source and have a more specific term when there is a need