That actually does make sense.
Square Enix has this propensity to announce games years ahead of time, and then not release them due to protracted development cycles- Final Fantasy 12, 13, 15, Kingdom Hearts 3, and Final Fantasy 7 Remake are all but a few games that have suffered this fate.
The latter two of those games are actually the two biggest games Square currently has in the pipeline- and both are currently languishing in development, even though Square Enix has recently committed to a 2018 release date for Kingdom Hearts 3. In spite of this, however, it seems as though development on Final Fantasy 7 Remake may actually be ahead of Kingdom Hearts 3, if only in some regards.
“Although there are also parts [of the Final Fantasy VII Remake] – such as cutscenes – that are ahead of Kingdom Hearts III, we’re in the process of switching from outsourced development to development in-house, so we don’t expect to release any relevant information for some time,” director Tetsuya Nomura (for both games) recently said in an interview with Weekly Famitsu (translation via DualShockers).
It does make sense in some regards- given how complex modern games are, a 1:1 comparison of how development is progressing is hard to make, so it’s not shocking that in some areas, development for Final Fantasy 7 may be ahead of development on Kingdom Hearts. That said, we can only hope that development on both proceeds smoothly now, and they both launch on time, as intended.