Nato may have the Edge in metals But china in this case as the edge in age. Tiger dates too 1990's, Apache too 1980's even with there updates the gun is still the Same. The WZ10 by contrast is a very recent type.
Bare in mind that 10 to 20 years can mean a lot in gun systems The Super cobra's M197 weighs more then the Comanche Prototype's Xm301 although the two are in fact related. changes in alloy and alterations too the operating group, Newer Alloys resulted in a lighter gun.The XM301 weighed in at roughly 80 pounds well the M197 146.3 pounds.
From the picture, it certainly looks less than 20mm... Probably WZ-10 indeed can fit a bigger gun but at what expense? More maintenance due to heavy recoil of tear and wear? Lower accuracy due to heavy recoil? Lower rounds count due to bigger calibre? Lower calibre will result more number of rounds carry. PLA probably do not see the need of their guns to take out armour vehicle.
Now we come back too the same old argument.
First Maintenance is always A must and will always be After every flight the PLA is likely already looking over there Birds So why is that a killer? Remember China has been using 23mm,25mm and 30mm in aircraft and Vehicles for decades. IT's nothing new they have plenty too use and as the Worlds Self proclaimed Factory Floor I don't think barrel and parts Supply is a major issue.
Second Accuracy (like everything else) is relative We are not talking about a sniper system we are talking about a anti vehicle platform. You don't need too put the round though the center of a tea saucer. A dinner Platter will Do. Lower round count yes but more effective rounds demand less rounds The HE punch of a 23mm cannon Shell or better will be way more then that of a 14.5mm.
Third Now we come back too it. the PLA does need too be able too take out Armored Vehicles with guns. Fact Missiles Fail! Fact there are only so many on the Stubs of A Attack helo less then most think. Given WZ10's weight class she packs around 8 antitank missiles Now 2 per Shot is about the norm for ripple Fire that means 4 tank kills assuming Murphy stays out of things and the missile functions as per advertisement. That is not much Especially when you start taking into account other details Like ADS systems And Air Denial Assets that can make the job more complicated additional Tank armor upgrades And numbers.
If you are up against a lightly mechanized force with just a tank or two and a handful of light APC's like say Vintage BTR's. You have it made but if it's True mech infantry Those birds are going too be busy and chewed up.
Next Trucks are not as light as they used too be. Thin skin is growing thicker.As the Hummer killed the Jeep, The MRAP is killing the Hummer. China Knows this they them selves are building Mraps.
The Technology of the MRAP came out of South Africa as such it's built too be Deployed and built with a moderate manufacturing capability. Many of China's Most likely opponents in Asia Already have MRAPS. Any fight in the Future that China Has too get into is going too involve Either Up armored trucks or True MRAPS and the bigger the Round the better the chances of a kill.