Not 100% sure...but they should be quite similar since they come from same base heritage. I doubt the Chinese back then saw fit to change much in the reverse engineering of that. Dont mess with the crucial life-dependent stuff unless you really know what you are doing and have time and money to do extensive testing.
Now you can always add more stuff on top (like say wire based actuators for redundancy if you are willing to take a hit on the weight and volume penalties (if its even possible to do so in the first place).
A somewhat interesting story is that they did this for the original B-52 when it was first introduced as the hydrualics felt too "Easy" for the pilots that had converted from WW2 era bombers....so they figured hey its extra redundancy anyway....and put in mechnanical actuators as well both to toughen up the feel and also act as backup.
As pilots eventually rotated through the generations, they changed back to hydraulic only with an upgrade and added redundancies based on that. Its always a lot easier and forgiving on a large aircraft when you have space and weight to work with.
On a fighter jet or small aircraft in general, its a premium....given the performance envelope is quite sensitive.
Yah I don't think its a maintenance based issue at all....given PAF and PAC are professionally run. It is probably a one-off unique thing given the age of the airframes/engines and certain small factors all coinciding by random chance. It will need to be investigated to see if any issue exists beyond age related general attrition.
Basically past a certain age, almost all aircraft (esp performance/payload based) are somewhat living on borrowed time. A dedicated maintenance and inspection/overhaul regimen can mitigate it....even substantially (though it depends, and the cost/benefit has to be analysed especially as time progresses)....but the basic issue will always be there given things like micro cracks, corrosion voids in inaccessible places (and complete change of these will probably cost more than just buying a new a/c).