theme_preprocess_hook_suggestion() does not override theme_preprocess_hook().

Given this implementation of hook_suggestions_page()

/**
 * Implements hook_suggestions_page();
 */
function mytheme_suggestions_page($vars, $suggestions, $hook) {
  $suggestions[] = page__my_page;
  return $suggestions;
}

I would expect mytheme_preprocess_page__my_page() to override (be called after) mytheme_preprocess_page(). This is not the case because pure_preprocess() (where suggestions are implemented) is called before specific hook preprocessors.