Cause the disparity between China and Japan is so high that it is likely China will quickly destroy most air bases and planes on the ground using its rocket force, and whatever planes are left will be quickly shot down by PLA advanced fighters. Once all the planes are gone, what defense does Japan have against PLA precision bombing using JDAM and glide bombs on the cheap?
These are questionable/overly simple assumptions. I understand that China made an incredible leap forward in 2010s-2020s, but this is justification for pride - not arrogance. Especially v. old enemy.
(1)Air bases can be temporarily put out of use by rocket force, but destroying airfileds is an altogether another matter. Repairs are effective, number of individual (and repairable) targets is just too much.
(2)Relatively simple dispersal can protect at least aircraft from such campaign, provided there's sufficient warning. Japan made signifiicant investments into ABM and air defenses, too. This doesn't mean they won't be overwhelmed, but it does mean that reliable hits will require overuse of limited MRBM capability (high tech SFREs aren't sausages).
(3)Japan is a large enough country, which is located far enough from China (like ~500 miles shortest for Home islands, but mostly more). I.e. Japanese fighters will be quickly attrited v. China only if Japan will for some reason go for it.
Japanese(and Korean) geography shields the former well from mainland China, at least until JMSDF/USN are alive and well. Things go south for Japan if DPRK and especially Russia aren't neutral, though.
PLA hypersonic anti-ship missiles will likely destroy all Japanese navy surface ships including those carriers. There is no hope for them to survive unless they flee to Hawaii. Cause Any place within the second island chain is in range for PLA anti-ship missiles. So, what utility do these carriers provide in wartime?
Range isn't endless killing field, and JMSDF ships are probably one of the best out there when it comes to ABM. They have multiple relatively safe havens(east coast; inner sea; sea of Japan behind Korea...depending on Ru/DPRK stance of course), where chances of succesful OtH attack on them aren't really worth a shot.