As of now vyos.configdict.node_changed() can only be used to detect if a direct child node (e.g. within a tagNode) is changed.
The helper should be extended with a recurse=False option (to keep current behavior) but to add support to traverse all nodes under the specified path when calling vyos.configdict.node_changed().
This should be no isse according to @jestabro now that the new config diff