Nikon is a large company with multiple entities. The main Nikon is composed of Imaging Products (cameras, lenses, sports optics) 45%, Precision Equipment (Lithography) 40%, Healthcare (Microscopes) 7%, and Industrial Metrology (Measuring instruments) 8%.
The Imaging Products used to be the core of the business but as camera sales plummet due to competition in the DSLR area, growth of the Mirrorless cameras and the fact smartphones have great cameras with software to boot, this division's sales have been shrinking, with no end of that shrinking in sight. Where before cameras were all Nikon or Canon, with a sprinkling of a few small brands, now it's Sony, Olympus, and the smartphones. The cameras are computers with lenses.
The sports optics was small part of the Imaging division and the spotting scopes, binoculars and rangefinders remain. Only the riflescopes are gone. It has been a long time since they were made in Japan. The few Nikon riflescopes that I have were made in Japan, but these are over 10 years old.
I have a Monarch Tactical 2.5-10X44 with a Mildot reticle. That scope is built like a tank and the glass is superb. I got it in '05. A couple years later they changed the name to the Monarch-X then it was discontinued. I have another Monarch, the 6.5-20X44, which was one of the scopes that was tested by that German Optics magazine in '07 and it was found to have better light transmission and clarity than all the other scopes they tested: a $400 scope beat out the S&Bs, NF, Swaros, Leupold, Docter, etc. They were shocked, in German of course, but shocked nonetheless.