In 2011-2012 they were under tremendous pressure to put out new DSLR products; the demand was high and people were expecting the D800 and D4. However, their manufacturing capability had been destroyed by three major natural disasters. I can understand why they made mistakes that then that led to quality problems in some products due to the circumstances at the time. It must have been hard to work if the roads and plumbing do not work and people are being evacuated because of radiation contamination etc.
This year there was also an earthquake, which may partly explain why some of their products are not released on schedule. But the real problem is not a delayed product but the release of products which are obviously not properly tested (Snapbridge, Keymission). This is likely to kill the Nikon brand name and people will likely see it as something to be avoided if the current practice continues. Then they won't be able to sell their good products which do work correctly, either, since people won't trust that they will.
I don't believe the development of a browser and a raw conversion software is an insurmountable challenge for Nikon. I don't think that it is too difficult for them to develop mobile applications that control cameras and transfer images. The problem is not the development of the software per se, but the attitude of the managers that it is perfectly ok to release products which do not work yet correctly. It's not an engineering problem if you release a product that doesn't work, it shows that management is not up to their task. They make the call when to release a product. And they've made a lot of really bad calls in recent years.
Thankfully the top of the line DSLR products and lenses seem to work as advertised, apart from Snapbridge problems reported by D500 users. I haven't run into any significant problems with their cameras, flashes or lenses myself since the D800 (mine had AF consistency issues though not the infamous "left AF" point issue). I've been very happy with their recent products actually, but am deeply annoyed by the quality of the software that they've put out since the discontinuance of ViewNX2 and Capture NX2.
I would be happy to offer my help in testing and providing feedback on their software in my normal computing environment, but they don't seem to be interested in receiving feedback from users. I really want them to get their software right. I don't mind using Adobe tools which do work correctly apart from Lightroom which often has serious bugs, but I need to see key hardware dependent parameters that are stored in the files such as active AF point, fine tune setting, and others. I would also prefer to see the images as shot in the camera using the full picture control settings information obeyed by default by the browsers and raw converters. That these do not work in Adobe software is a major annoyance to me. I now use control points in Nik / Google plugins but their use is a lot slower than use in the Capture NX2 software and I find making local adjustments is a slow process now, and feels very primitive. The file sizes also become astronomical if I want to preserve the full bit depth and not subject my images to compression artifacts.