jackson-databind 2.3.0 or later, POJOPropertyBuilder lines 681-688 says:
        String explName = node.explicitName;
        ...
        // different from default name?
        if (explName.equals(_name)) { // nope, skip
            continue;
        }
 
but _name is of type PropertyName, so this check is always false. That's why all properties are marked as "renamed" in method findNewName().
I would have sent a patch but I don't know what's the right way to fix it.