Thanks for your request. You are right, currently there is no way to remove styles from the document. Your request has been linked to the appropriate issue. You will be notified as soon as this feature is available.
Best regards.
Thanks for your inquiry. The RemoveUnusedResources method was added to Document class to remove any unused styles and lists from the document. Please try run the following code:
Document doc = new Document();
doc.RemoveUnusedResources();
doc.Save("");
Starting from Aspose.Words 21.4, you can remove unused built-in styles from document using CleanupOptions.UnusedBuiltinStyles property. Following code snippet shows how to use this property.
Document doc = new Document("input.docx");
CleanupOptions cleanupOptions = new CleanupOptions();
cleanupOptions.UnusedBuiltinStyles = true;
doc.Cleanup(cleanupOptions);