In the realm of XML schema visualization and editing, several existing tools have aimed to provide support for navigating and understanding complex schemas. Oxygen XML Editor, Altova XmlSpy, and Liquid XML Studio are among the notable tools in this domain. While these tools have made significant contributions, over time they have gained so much complexity that they can be quite intimidating on first use and due to the density of features the main purpose of a visualizer software - giving a clear overview - gets lost.
Here is a screenshot of XMLSpy, for example. When opening the RSS format XML schema. While the visualization of the schema is a good start, there is a lot going on around it that can be quite intimidating and lets the user question where to go next.
In the next screenshot the channel element is open but because of the annotations the graphic gets so big that it cannot be shown entirely on the screen. While there is an option to hide the annotations, this is the default behavior and the user has to search for the option to make the visualization more readable.