With T161543: Enable geoshape datatype on Wikidata there will be a new datatype around meaning pywikibot will cry whenever it encounters a page with one of these.
From pywikibot's point of view this should be similar to how Commons-media was implemented.
However the big difference is that we haven't implemented a DataPage class (or a map subclass of this) to deal with the new capabilities on Commons.
An alternative (or temporary work around) would be to create a new type in __init__.py which takes a normal Page object but validates that it has the Map.JsonConfig content-type* (or any other restrictions, such as namespace, implemented by Wikibase).
- Wikibase checks that the page exists on Commons and that the title fullfills '/^Data:[^\\[\\]#\\\:{|}]+\.map$/u'