The usual excuses...[machine translated interview, published 26 January 2023]
"However, there is still a shortage of some materials, especially lenses, which continue to cause customers to wait for a considerable amount of time. One of the reasons for this is that the transition to the Z system has received more support from customers than we expected based on past figures. The "NIKKOR Z 600mm f/4 TC VR S" released in November is a lens that costs more than 2 million yen, but we received far more orders than we expected based on past experience. Regarding products that have been kept waiting, we will strive to improve so that we can deliver the products as soon as possible... "
Takuhide Tsuji, Director and Executive Officer Director of Marketing Headquarters
https://www.phileweb.com/sp/interview/article/202301/26/915.html
Also
https://digicame-info.com/2023/01/post-1610.html