I assume that the return on investment should be expected when the first thousand or so cameras have been sold. The break-even point is around 1,500 examples.
This is a completely small amount. Personally, over the years of my work, I have restored about two thousand cameras, and I am of course not the only one who restores classic cameras.
I am often approached by people with questions about what kind of camera they should buy, explaining that they are not collectors, but want to shoot on film. They need a quality and reliable film camera they can trust. They are interested in shooting, not in the collectible value of the camera. They want results and reliability.
The number of such people in the world is growing. An indirect way of confirming this is the production of photographic films since 2015. After a catastrophic fall in the first decade of this century, a gradual increase in production has been noted since 2015. (I will add growth statistics for film production here a little later)