Has the Block Cache Settings from Drupal 8 been back-ported to Drupal 7?
No, it's impossible to backport. See https://api.drupal.org/api/drupal/modules%21block%21block.api.php/function/hook_block_info/7's DRUPAL_CACHE_CUSTOM and https://www.drupal.org/developing/api/8/cache/contexts.