comment subscription custom post type

Is there any reason why the jetpack subscription only works with posts and not custom post types? I am having the comment forms on posts and cpts but the checkbox only appears on posts :(. i digged into the subscription.php code and discovered this line of code:
if ( FALSE === has_filter( 'comment_form', 'show_subscription_checkbox' ) && 1 == get_option( 'stc_enabled', 1 ) && empty( $post->post_password ) && 'post' == get_post_type() ) {

so for some reason you are limiting this feature to posts only. why?? i really need it for CPTs. Thanks!

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