Think I am a perfect example as to why Nikon sales have slumped. As a almost 30 year Nikon only shooter with 3 Nikon bodies and 22 Nikkor lenses I almost gave up waiting for Nikon to go mirrorless, and when they finally did, I did not like what they gave us and went elsewhere. Back in late 2012 I added Olympus M4/3 to my Nikon gear, as my yearly trips to Thailand (Thai wife) with my Nikon D700/D800 and heavy lenses was just no longer practical due to airline weight restrictions. My lightweight EM5/EM1 bodies and the numerous small and compact f1.8 lenses were perfect for this. It really opened my eyes as to what Mirrorless cameras could do. But I missed shooting with my D800 and getting the high MP and finally after 6 years, Nikon announced the Z6 & Z7. This came 5 years after Sony announced its first A7 & A7R FF high MP mirrorless bodies in 2013.
What I saw was that the initial Z cameras were priced like Nikons high end DSLR cameras, but crippled by lack of features, supposedly to protect the DSLR market. The nail in the coffin (for me) with Nikon though was their lack of AF support for the Nikkor screw drive lenses, as I had 7. Nikon even today continues to sell AF screw drive lenses, like the 135mm f2 DC, 180mm f2.8D and 200mm f4 Micro with no new replacements in sight, yet they still refuse to put a screw drive motor into the mirrorless body, as they did in the D7000 series. If they could add this motor to a $900 DX body, they surely could have added it to a $2,100 and $3,400 Z body. Or at least put out an adapter that had the necessary motor. Instead they left me, and the owners of 4 million Nikkor screw drive lenses hanging.......
So I went with a 24MP Sony A7III in 2018 and then added a 42MP A7RIII and could not be happier. Meanwhile Nikon 2 years later in late 2020 announces the series II of the Z6 7& Z7, which in my opinion is the cameras they should have announced back in 2018. And they still don’t offer 3rd party lens support, which is a huge advantage of owning Sony A7 bodies. Nikon it seems still does not get it and if they do indeed go out of the camera business it is 100% the fault of their management with their backwards and protectionist thinking, where their long time existing customers were put last in the rapidly changing camera market.