When it comes to describing the central theme or purpose of something, "what it's about" is a commonly used expression. However, there are a variety of synonyms that can be used to convey the same meaning. For example, you could say "the crux of the matter," "the heart of the issue," or "the main point." To emphasize the significance or relevance of something, you might instead use phrases like "the bottom line," "the key takeaway," or "the essence." By considering alternatives to "what it's about," you can communicate your thoughts and ideas with precision and clarity.