@Antares545 , first of all it is CIWS, not CWIS.
Generally speaking, the reason most navies do not pursue up arming major combatants with more of these types of weapons is two-fold. They don't think more are necessarily cost-effective for the task at hand, and they also prefer to not have to rely on them anyway.
Large missile saturation attacks is not a new concept or thing, back in the cold war days it was considered a major threat. The soviet navy doctrinally fielded more CIWS systems per ship, but this was done because their accuracy was expected to be much, much lower than comparable western systems. Nowadays, they are back to 1-2 systems per ship in new construction projects.
The idea that PLAN is throwing caution in the wind for not fielding more CIWS systems per ship is in my honest opinion misguided. By doubling the number of CIWS per ship you are not doubling your defense capabilities. That is not how missile defense works.
Lastly, I suggest you consider adjusting and policing your prose, before you get banned for shitting up a flagship thread like this. cheers.