No "type" of metadata is a distinct subset of metadata. Take these three scenarios.
Copyright metadata restricting the viewing of a video.
Location metadata recording the location of an image referenced in an HTML file.
Format metadata describing the version of software used to create a CAD file.
Each of these pieces of metadata have been categorized both as preservation metadata and another type of metadata (rights management, structural, and technical) by the community at different points. That's not to say that preservation metadata encompasses all metadata. I'm sure there are valid arguments that it might be. Similarly, there are valid arguments that descriptive metadata, technical metadata about digitization, or other metadata might or might not be required for preservation.
Each "type" of metadata is most useful as an internal shorthand what that type of metadata has been defined to be. Outside of a specific organization or context, don't trust that you are speaking about the same metadata elements just because you're discussing the same "type."
If you are thinking about what defines preservation metadata for your context, I like the NDSA's definition. "The contextual information necessary to carry out, document, and evaluate the processes that support the long-term retention and accessibility of digital content."