Return with custom prefix text:

add_action('single_term_title', 'single_term_title_28072021');

function single_term_title_28072021($term_name){

    $queried_object = get_queried_object();
    $taxonomy = isset($queried_object->taxonomy) ? $queried_object->taxonomy : '';


    return sprintf(__('Product Category: %s','textdomain'), $term_name);

}

Return with taxonomy prefix text:

add_action('single_term_title', 'single_term_title_29072021');

function single_term_title_29072021($term_name){

    $queried_object = get_queried_object();
    $taxonomy = isset($queried_object->taxonomy) ? $queried_object->taxonomy : '';


    return sprintf(__('%s: %s','textdomain'), $taxonomy, $term_name);

}