public Boolean getBooleanObject(String key, String description) {
    var arg = getArg(key);
    Boolean value = arg == null ? null : "true".equalsIgnoreCase(arg);
    logArgValue(key, description, value);
    return value;
  }
Returns a boolean parsed from {@code key} or {@code null} if not specified.
planetiler-core/src/main/java/com/onthegomap/planetiler/config/Arguments.java