On profile update check if user is Subscribed to emails?

Roles in wordpress are case sensitive, I used the lowercase text for the same.

Your function must return a value.

    add_filter('insert_user_meta', function ($meta, $user, $update) {
    if (true !== $update) return $meta;

    //Check 'email_subscriber' meta-key for the user
    $email_subscriber_meta = get_user_meta($user, 'email_subscriber', true);

    // Check the user if it is subscribed by meta-value if checkbox value is something else replace 1 with that value
    $is_email_subscriber = !empty($email_subscriber_meta) && $email_subscriber_meta === '1';

    if ($is_email_subscriber) {
        // Add the role incase itdoesn't exist
        if (!in_array('email_subscriber', $user->roles)) {
            $user->add_role('email_subscriber');
        }
    } else {
        // Remove the role if it exists
        if (in_array('email_subscriber', $user->roles)) {
            $user->remove_role('email_subscriber');
        }
    }

    return $meta;
}, 10, 3);