I don't see any reason why china needs that many aircraft carrier in order to defeat Taiwan and even Japan and usa. Taiwan is obviously very close to china that even J 20 can strike that nation. And let's be real, once Taiwan is captured I don't see any reason for Japan to continue fight. Their morale is going to be heavily decreased. So again what's the need of 10 aircraft carriers? Are they fighting a nation that is very far away from them? Right now the advantage is on china side. Unlike america, china can fight 100%. Whereas america has to depend on their allies to strike china. They are not going to send all their fighter jet and aircraft carrier for war against china.
If US is fighting, then Japan is guaranteed also fighting or they are in the China camp. Neutrality is simply not an option.
Moreover, US and Japan and most likely also Australia, will disperse their force all over Japan in order to mitigate PLA rocket force strikes. Russia has fired thousands of missile and still they haven't been able to fully destroy Ukraine's air force, missile or any other significant military formation. This is due to dispersal and concealment.
China lacks the numbers to saturate Japan with rocket force. According to pentagon they have about 1000 launchers that can reach japan and about 2000 actual missiles. So, just 2 reloads per launcher. There is a reason for this, ballistic missiles are expensive.
China lacks the necessary numbers in air force or rocket force to strike a vast country as Japan. So, they will have to fight it out in the air against combined US+Japan+Australia+Taiwan air power. Its like 4000+ fighter planes.
I have discussed this before that US can also bring not just active service planes, but also its vast arsenal of retired 4th gen planes from the boneyard. China doesn't have that stock. So, they must have a bigger active service planes to overcome this gap.
Finally, when it comes to the navy we cannot assume all naval battle will happen close to Chinese shores, China might be forced to fight in the high seas. WW1 and WW2 naval battles have shown that the navy with the bigger fleet usually wins. US has big carriers with 100s of planes per carrier. Yes, they cannot bring all 10 due to maintenance issues, But China can also not operate all of its carriers at a time. So, if US brings 5, China needs to be able to bring atleast 7-8 carriers. So, their total fleet needs be bigger than 10..