The MG-42, K98k, MP-40, Panzer IV, StuG III, Bf 109, Fw 190, Type XI U-Boat, and S-boat would all like to have a quick word with you.
EDIT: the Hs 123 was replaced by the Hs 129, which turned to be absolute shit in terms of performance.
The A-10 continues to exist for the same reason the Russians still use the Su-25.
Both the A-10 and Su-25 are effective battle tested aircraft.
On the other end, we have the Chinese JH-7. At least 6 have crashed for a variety of reasons, the design is godawful, and the quality is abysmal.
It's unfortunate that US planes were the direct counter for Japanese planes.
Powerful engines, fast, heavy armor, lots of .50 MGs.
Zeroes would often run out of ammo when fighting Hellcats and Corsairs.