Seeing the news about E-2Ds replacing the E-3 sentry, I think KJ-3000 is DOA, there simply isnt a need, more KJ-500 equivalents is better, with higher uptime, more attritable and more flexible operating off short runways. The USAF is moving to an AWACs system more similar to China's current set up. Numbers > individual performance in many such cases.
You have not interpreted that news correctly.
First, the E-2D "replacing" E-3 has yet to be set in stone -- and it is less that the E-2D is replacing the E-3 as a proposal but rather they are proposing cancelling the USAF E-7 buy and using E-2Ds as a stopgap until a space based AEW solution comes into play.
E-2D very much is not a replacement for E-7 and is inferior in many respects.
For the PLA, remember they already have something like 70-80 land based AEW&C, of which the majority are KJ-500, with KJ-700 and KJ-200, and four large KJ-2000s.
That is to say, in terms of "numbers" they already have the numbers, and are unlikely to reduce their AEW&C fleet size any time soon, and those platforms they have are credible medium-heavy platforms, of which the majority are turboprop powered (which offer some benefits and some disadvantages relative to turbofan airframes)
KJ-3000 otoh is a much larger, genuine heavy airframe that is powered by turbofans. They are likely not going to fill the same role as the PLA's existing medium-heavy platforms, but serve as a higher echelon AEW&C platform that offers not only more modern technology, but also greater airframe capacity for carrying consoles, onboard processing, EW, power generation, etc.
In other words, KJ-3000 should be viewed as a "luxurious" high end AEW&C product that only makes sense if one has been able to fulfill the "bread and butter" AEW&C fleet in sufficient numbers. Fortunately for the PLA, they have achieved the bread and butter AEW&C fleet. In fact, the PLA's land based AEW&C fleet is probably the envy of every major air force in the world in terms of scale and sophistication.