Not much of a problem seeing as software version 4.05 is pretty old, PS4 is currently on version 5.05 and anything older doesn’t let you online.
It should matter. Any game released after firmware 4.05 will not run. If nothing has changed from previous gen console hacks the (hacked) firmware version must be the same or higher than the one who was the current when the game you are trying to play was released.
It seems to be the real deal. apparently they used the kernel exploit to get root to the device, so they can basicly install anything. He was showing uncharted 4, gta5 and diablo3, but like has been mentioned , newer games wont work anymore. oh and the ps2 emulator totally is broken also.