That's like tv news calling every Russian fighter a MiG!
To us that's heresy. But sad to say, it doesn't insult the intelligence of the general public.
Calling an Oscar, a Zero is the same as calling a Spitfire a Hurricane. See what the RAF pilots would think of you then.
An A6M 'Zero' is answering the same criteria as it's Army rival so the Ki 43 Oscar has similar broad strengths and weaknesses (Like a P-39 and P-40 in their own way).
Now I am tempted to point out a few pertinent differences. The Zero had 4 guns, 7.7 mm and 20 mm and no armor till 1944! Then some 13.2 mm started replacing the 7.7 mm and armor protection was added incrementally.
The Oscar took a different approach. It started out with armor (by Japanese standards) and had only 2 guns for the duration of the war! It skipped the low ballistic 20 mm and started with the 7.7 mm cowl guns, then one 7.7 mm and one 12.7 mm, then twin 12.7 mm. The twin 20 mm guns were late comers.
The appearance was similar but for the tail. The Zero had that Mitsubishi cone tip like the A5M Claude before it and the J2M Jack that followed. Niether of these Mitsubishis would be mistaken for a Zero by a trained pilot except head-on at a distance. Maybe.
But the Oscar is a Nakajima fighter with the slightly rounded rudder shared by that family of fighters, from the Nate to the Frank.
It reminds me of the Ki 61 Tony misidentified as a German Bf 109 (or Italian Macchi C 202 - hence the code name Tony) in Japanese service or else a copy, as if it wasn't their own Kawasaki design around the same inline engine.
The fact that it took air superiority away from the US fighters when it appeared in the Pacific may have had a little something to do with this WW 2 propaganda. To this day some Americans still believe it. I need a drink!

In addition to "Oscar", the Ki-43 was commonly nicknamed the "Army Zero" for it's resemblance and similar performance characteristics to the more famous Navy A6M.

Everywhere you look the books say the Ki 43-II used two 12.7 mm MGs in the cowl, unless you look at the evidence at the combat fighter bases. It seems these Browning based Type 1 Ho-103 heavy machine guns were too unreliable and slow so the field crews replaced one of them with the old reliable Vickers based 7.7 mm Type 89. At least the early Ho-103s risked shooting down their own Oscars, so they protected the engine from the gun's misfire, with armor.
Judging from their sister Italian weapons, the Breda-SAFAT 7.7 mm and 12.7 mm with the same ammo and lineage, I estimate these synchronized cowl guns may have fired at the rate of 700+ r/m for the 7.7 mm, and 450 r/m for the 12.7 mm IJAAF guns. Both 7.7 mm guns were vickers by design and both 12.7 mm guns were Browning (but the Breda was reliable). Does anyone know the real rates?
We know that the synchronized Bredas fired 665 r/m ave, and 575 r/m ave. respectively and unsynchronized they fire 850 r/m and 700 r/m while the faster Japanese versions both fired 900 r/m. Obviously the IJAAF was impressed with prewar Italian MGs and ammo. Small exploding rounds were effective against fighters of the 1930s but the metal skinned fighters were another story (not to mention bombers). Tachikawa was the main builder of production Ki 43-IIIa fighters. But it was the -IIIb that got the 20 mm Ho-5 twin cannon and these were only prototypes.

I love this Ki-43. And this teknikal date. And Ki-43 figter ess.

There are several subtypes to the Ki43II, without official designation changes. The very first type had full span wings like the Ki43I. This type recorded a max speed of 515km/h. The next variant with clipped wings recorded 530km/h. With the "rocket" exhaust systems fitted to later models, the figure went up to 548km/h.

Also, although the number of Ki43IIIs completed is not clear, it seems to have been available in substantial numbers from late 1944. Tachikawa took over Ki43 production after the introduction of the Ki84, and they built about 2500 Ki43s (no subtype information available) so I would not be surprised to see at least a 1000 Ki43IIIs manufacutred. Units like the 64th Sentai chose it as their replacement for the Ki43II over the Ki84 and all of their front line machines were Ki43IIIs by the war's end. Many Kamikaze unit photographs equipped with the Ki43III also exist so they did see substantial action in combat during 44-45.