Interesting video; I've never seen any complete (let alone working) Monophoto machine in real life.
The first generations based on the composition caster's mechanisms were a rather short-lived technology. I've seen some parts from one such machine, and one or two diecases for it.
To be honest, I can hardly see a use for them now. You need a source of material (good luck with that - even regular 36mm or 60mm photographic film and paper is expensive nowadays), darkroom, chemicals etc. If the effect is the same, then cheaper means (e.g. DTP program and a laser printer) to reach it win. And the mistakes are a pain in the arse to correct; mistyped characters (especially on Monophoto keyboards) don't come up until you process the film. The composition caster at least lets you replace the wrong characters by hand.
The system had its advantages back in the day, if you had a lot of work to do. The speed didn't depend on type size, developing the film was easier if done as a batch process and chemicals would be used faster than they expire. It all made the process good for newspapers/magazines, publishing houses etc., but not small fine book printshops where hot metal is still used nowadays.