D6 Date fields not getting picked up by `drush migrate-upgrade --configure-only`

If I run drush migrate-upgrade --configure-only, using a Drupal 6 DB, and then run drush mi --execute-dependencies upgrade_d6_field the date fields are not getting picked up, and will not get migrated. They simply get marked as ignored.

I can realized that the field type date and datetime is not recognized by cckPluginManager nor the StaticMap.

I think that I can work around this by making this dirty change to this class, but that is obviously not a solution:

# /core/modules/field/src/Plugin/migrate/process/d6/FieldType.php
public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
  list ($field_type, $widget_type) = $value;
  try {
    $mapped_to_field = $this->cckPluginManager->createInstance($field_type)
      ->getFieldType($row);
  }
  catch (PluginNotFoundException $e) {
    try {
      $mapped_to_field = parent::transform($value, $migrate_executable, $row, $destination_property);
    }
    catch (\Exception $ex) {
      if ($field_type == 'date' || $field_type == 'datetime') {
        $mapped_to_field = 'datetime';
      }
    }
  }
    
  return $transl_to;
}

I don't see any migrate plugins at here.

Are there no migration path for date fields yet?