Both F35 and F22 have provisions for oversized stores by external hard points, the Adaptability would in theory be in external pods that would sacrifice RCS for additional equipment. It has degrees of radar cross section reduction but so do the latest iterations of 4th gen F16 and F/A18.On the other hand, it gets to be readily adaptable, by definition obtains more external stores, and carries oversized payloads w/o any issues.
Fifth generation fighters combine a EW suite and Stealth shaping + materials to get the best of both. The EW suite allows the pilot to move his machine in a manor so has to get the most out of his stealth. By using external stores in the way the KFX aims to the ability is sacrificed to a farther degree.Since it is designed to be seen, such aircraft is likely to be more survivable when it's the case(it's the hypothesis behind its EW suite, after all).
Where an F35 might be able to pass a radar at 50km with internal only loads, an External loading sibling has to fly by at say 100km this probably more like 150km. To avoid detection. The claim made that none stealthy would be more survivable is questionable at best. As EW is what stealth is. Stealth as we know it today is a combination of passive and active electromagnetic signature control.
We are here I think kinda agreeing, the KFX seems tailored to allow ingress and egress vs the low end Air Force and air defense capabilities often seen in the third world. This makes sense as the most likely target for use of it would be the DPRK. With the exception of Pyongyang the air defense of the nation seems rather poreus. Vs the antique Air Force of MiG 21s these would likely hold there own well higher end F35 could take higher risk targets around the central capital with its fortified air defenses and Mig29s.Finally, while not a true stealth, some of its aspects(and empty or near-empty configuration) may be decently stealthy, maybe even within realm of true stealth aircraft. Egressing from the battlefield, or, say, ambushes from low altitude using outrageously long burn of meteors come to mind.