// Get the default value for this field on this bundle.
$field_default_tags_value = $field->getDefaultValueLiteral();
$field_default_tags_value = $field_default_tags_value[0]['value'];
// Get the default value for this field on this bundle.
$field_default_tags_value = $field->getDefaultValueLiteral();
$field_default_tags_value = $field_default_tags_value[0]['value'];