An amateur way to put a case into perspective, If JFT is so inferior, why PLA is still flying obsolete Q5, J7s and J-8IIs? Are they on par with J-10s aerodynamic performance? NO!
It all comes down to requirement, look at the projects they have under their belt, from J-20 to J-30, to J-11 xx, 15, 16, JH-7xx and what not. If you had any idea how much money, resources and time a single project R&D costs...
JFT perfectly fits the PAF, almost by default, a highly agile 4th generation aircraft that has a hostile neighborhood with plenty of toys to play with.
For PLAAF, the situation is much worse, they have Uncle Sam, Japan, Taiwan, India, even Vietnam in the backyard so they need heavy, long range and advanced aircraft in service ASAP.
Lastly, despite all this, the ground attack variant is still an option for PLAAF as a replacement for Q-5 and possibly for J-7s since they have not ruled it out and are still testing it.