This problem might cause a ripple effect on the sale of PS5 when it will be released. This simple hack might mean that the PS4 is easily infiltrated and vulnerable to more complex attacks.
This will hurt Sony a lot, especially when there is a gossip that PS5 is "expected" to come out next year or by early 2020. Sony has to make sure that their system is safe or else many gamers will move to Xbox or PC platforms.