default O getOrElse(Map<String, Object> tags, O defaultValue) {
      List<O> matches = getMatches(WithTags.from(tags));
      return matches.isEmpty() ? defaultValue : matches.getFirst();
    }
Returns the data value associated with expressions matching a feature with {@code tags}.
planetiler-core/src/main/java/com/onthegomap/planetiler/expression/MultiExpression.java