I guess you need tools like rqt_graph?
ros2/ros_network_viz (github.com)
Introducing ros2_graph - General - ROS Discourse
ROS diagram tools - ROS Projects - ROS Discourse
New visualization for ROS 2 systems: Call for datasets - General - ROS Discourse
iwatake2222/dear_ros_node_viewer: Dear RosNodeViewer: Visualize ROS2 Node Graph (github.com)
there are also many other TUI/CLI Tools rather than GUI that can help you inspect the runtime arch of ros2 system.