They have over 3500 aircraft, although a large percentage of them are outdated and almost all of the types used, except for a relatively small number of Russian imports, are untested in combat. Their operational history is universally one of accidents and/or dangerous provocations. Expect even the latest types, which appear modern on paper, to lag at least a generation or more behind any current Western designs in actual capabilities.
It also doesn’t help that there is no institutional knowledge due to a complete lack of combat experience anywhere in the PLAAF, that Chinese military pilots are poorly trained and that China appears to have no ability to deal with American countermeasures and tactics, as evidenced for example by their chaotic and unsuccessful attempt at intercepting Nancy Pelosi’s flight to Taiwan.