It seems like having the
import-wizard tag would be sufficient, and that we don't need
data-import-wizard. The former is the more heavily used tag.
Once upon a time, there was a feature of Salesforce referred to as "Interviews". Those were Visualforce pages strung together consecutively with a purpose. Many developers create those on their own using custom controllers. The feature itself has now "morphed" into what we now know as "Flows".
There are other things that are "imported" into Salesforce, including "files" or "documents"; sometimes as attachments, sometimes as "content", or perhaps as "knowledge". Some, might think of those as just another "type" of data. However, the standard data-import-wizards don't support files or documents at this time. Some developers, may have created "wizards" for this purpose or may have questions about creating a custom "import-wizard" for their organization or as an application they intend to offer on the App Exchange.
I can see a sufficient distinction between the two that's sufficient to justify keeping both of them. Remember, this is more of a developer forum than it is a "user forum" where questions about using built-in features would be asked as they are in the Trailblazer Community.