Please show me where John says “new covenant world”; all I see is ὅλου τοῦ κόσμου, which is literally “all the world”. Moreover, “all the world” is contrasted with “and not only ours”, which means “all the world” cannot refer to believers, which “ours” means.
There is no distinct designation that qualifies “all the world” as all the covenant world. The syntax does not allow that!
Doug