Since the small 35mm frame gained popularity in the mid-1900s, it is well known (and perhaps lamented) that the particular crop factor became a de facto standard in the late 1900s, when people have discussed their fields of vision, which is useful for talking compression compositions and other related things.
Nowadays it can be said that he has a "35mm lens" while he's bought a micro-4/3 lens with a focal length of 17mm. Maybe not technically correct, but as a "standard", 35mm equivalence makes sense. You know what type of field of view a 35mm lens is sporty.
How were these conversations at the coffee machine at the time, before 35mm took hold of the world?
Was it just like "good I have this lens here says 200 mm on the side and it makes a very good portrait" and what would be the end of that? 🙂