NX Studio is the only current editing software.
Capture NX-D can be found mirrored on some legal download sites. It is, however, abandonware.
If you like the results from shooting jpg but want the flexibility of shooting in raw, NX Studio does a better job than third-party raw-converters.
Affinity works really well with the older NEF formats from a D800 or a D810. It works acceptably well with the D850 files but I can’t get the result I want with Z6II or Z fc files.
My choice of raw converter is PhotoNinja. It lets me expose for a part of the scene and then tonemap the rest where I want it to go…
This scene had a nicely exposed sky but the buildings were close to black SOOC…