The average person might think that the more experienced an editor is, the more edits that editor is going to make, but the opposite is often true.
Sure, experienced editors are typically more knowledgeable about what to look out for in a manuscript, but they also know what NOT to edit, when to leave things well enough alone to preserve author voice, especially when working with fiction authors who are self-publishing.
Editorial restraint is a valuable skill, and seasoned editors are usually experts at using it because it takes time to develop.
Timothy