On humorous side notie, it looks like the liked "Ministry of Culture’s own published guidance on the proper formatting" [0] has auto-translated Nikon's .NEF RAW file format extension into .NAVE without any editor noticing.

Also, these RAW formats do support compression, in some cases even lossy modes.

[0] https://cosmowenman.wordpress.com/wp-content/uploads/2026/09... - page 54/55 screenshotted in the article.