Here's my take on the demise/rumored demise of the Ruger No. 1.
Probably 95% of my rifle shooting is with a single-shot original and reproduction rifles: Winchester m1885, No.1, Remington Rolling Blocks, trapdoor Springfields, Sharps-Borchardt, Ballard, Martini-Henry, Browning-Miroku 1885, and Shiloh- Sharps m1874.
In my opinion and experience, single shot shooters are scarce and dying breed. Single-shot shooters fill a small niche of firearms sales. And that is the problem with the Ruger No.1 -- too few buyers. In addition, after awhile, a great number of the No.1 shooters had or just about had all they wanted or could afford and the demand tapered off. A company cannot stay in business by tooling up and selling small lots of rifles or those with a limited demand.
At the approximately 1500 member club that I belong to, I shoot two days a week, sometimes three, between early April to early December. I am the only single shot shooter that I see on the firing line. There a few others, but they are Black Powder Cartridge Silhouette competitors who very rarely use the range. And I do not know or heard about any other Ruger No. 1 shooters who are members!