“The way he managed to beat a trillion dollar corporation was through the kind of simple but tedious and boring work that Apple sucks at: regression testing.”
The 2020 unc0ver jailbreak for iOS 13 was the last public 0day jailbreak on current iOS. The bug was one Apple had already fixed and then shipped again. Pwn20wnd found it by rerunning old exploits. Apple had already done the same thing with SockPuppet a year earlier.