On the subject. There is an analytical article on the Chinese web that may be relevant. I will paraphrase the general meaning of this article.
In the beginning, China actually had indigenous advanced air defense systems. However, the area we need to defend is so large that there is a severe shortage of new domestic air defense systems being produced. So, China purchased six S-400 air defense systems from Russia for a total of $3 billion. (The total price tag for India's purchase of five S-400 air defense systems is $6 billion.)
When the PLA received the S-400 air defense systems and tested them, they found that their true capabilities were far from what Russia claimed. In particular, the radar's ability to discriminate was very poor. It is much worse than China's own air defense systems.
At that time, PLA had considered upgrading and modifying these S-400 air defense systems on its own using Chinese parts. However, after careful accounting, it was found that the cost was too high and there was no value in upgrading.
Therefore, PLA transferred these S-400 air defense systems to secondary areas to perform operational readiness air defense tasks, while the operational readiness air defense tasks in China's main areas were undertaken by China's own air defense systems.------The original plan was to use these S-400s for air defense missions in key regions.
Both China and India have S-300/400 air defense systems. So PLA is fully aware of the real capability of these air defense systems and not the paper strength claimed by Russia/India. So, PLA is fully aware of how to circumvent these air defense systems.
So, due to the presence of Chinese military advisors, Pakistan can choose its attack methods and attack weapons very accurately.