The story from something in Italy is already some years ago. And I also know from accidents where it were other agencies. Totally offtopic.
Back on topic:
The ccr cave course wasn't there before around 2010. Then it was introduced. So a lot of divers already dove with ccr in caves. There is an evolution going to make new courses. The reason: People want it or some need it.
It already starts with something like a drysuit course. A drysuit can be a dangerous tool if you don't know how it works. But it is no rocket science. If you ask if it is needed, a lot of divers will say use a buddy to help you, a lot of instructors will say yes, for sure you need a course. But do statistics really show that divers with a cert have less problems?
I am not against courses. But in diving there is no option to be self teached. So autodidacticals are the bad ones in the diving world. And that is not always true in my eyes. I am not directly pro self teaching as this can become dangerous. But the judging on internet and social media is too hard. There are standards and if a standard states something is allowed, why then discuss this always as wrong? If you dont' agree, found your own agency. Sometimes I whish there is something as an exam possible to check if divers know their skills already, but the judging must be done independent. This exam must be an option with the newer courses that become mandatory now, but weren't there when the diver started to do the dives.
There are quite famous cave divers without a cert. And then nobody is complaining. Why not? They have done cave rescues, done exploration, etc. Oh yes, these are divers that know what they are doing.
But why are there other divers that are less known not knowing what they do? Do you know for sure that these unknown divers don't know?
I absolutely think that if you want to dive in caves you need a complete cave diving course. This is like getting a driving licence. You need to take lessons, do an exam, even if you have a big yard where you already use a car for years on your own private property. You know how to drive a car, but you take some lessons and an exam to show that you know the rules also. For ccr cave after oc full cave, I think just a crossover is enough. And maybe some don't need it anymore because they already do it, especially the older generation when there was no ccr cave class. A complete new cave course is not needed, normally you would already know about swimming speed, navigation, gas consumption, siltouts, line protocol, etc. That is not new when diving a ccr. The new things are the scr bailout practise, the bailout gas choice (not all gases offer the scr option), another way of thinking about gas rules, teambailout vs individual bailout, etc. So normally the divers are already experienced in cave diving and the instructor need to review the ccr skills and focus on the new things. This is how I learned it to teach also. Do a skill review in open water, then go to a cave, repeat it overhead not far from the entrance, then focus on the differences.
BUT: a crossover to ccr can only be done if the diver is really familar with his ccr. So some cannot do this with the minimum of 35 hours on the unit.
I normally do a 'let know each other and determine your level' dive not far from home. And yes, I have said to people no after this dive. But I have also had divers that already readed all the theory, the crossover was just a do it. That is also not the hardest work for an instructor. The hardest students are the ones that are not ready or have really bad basics in diving. And then also have a 'yes but' mentality, everything that goes not as wanted is not their fault, but the buddy's fault, the material, the cave, the drysuit, the etc etc etc.
But remember that new courses are written. Partly for safety, partly to earn money, partly because divers ask for it. Courses are part of a business model of every agency. Every agency makes new courses. No sidemount? Divers want to do sidemount and go to an agency that offers sidemount. No ccr? Divers go to an agency that offers ccr. And you see all the agencies grow more and more together with their standards, courses and certs. For recreational diving there is the WRSTC. For technical diving this is not organised this way yet, but you see that the courses are not that different between most agencies on more or less the same level just to make hopping from 1 agency to another possible.
But a lot of newer courses are developed by the 'you do this already, can you tell me about that? ' way. You are a photographer, so you explain in your club in 1 evening about photography, composition rules, the housings, strobes and knowledge is shared. Then people want that you help them under water, and you do it. You see people without trim and bouyancy damaging the corals, so start also pay attention to this. People forget their gas consumption, you think, this can be dangerous. Then you think because more and more ask you the same questions, I have to write a course and a photography course underwater has been born.
I also see now for example a course to learn how to use a bailout ccr. I already use 2 ccr's sometimes, a long time before the courses were written about this, so have tried all the things out myself to know what works and what not. I learned it the autodidactical way. This was maybe a longer way to learn, but there was nothing else. And others asked me about the problems I found, so I explained. Sometimes they tried and we shared experiences, and then somewhere a diver came with the idea to write a course. The course directly tells you what works and what not. So most of the few divers who are using a bo ccr now have learned it by self teaching. The newer generation will learn it from a course.
So if you had as instructor for a crossover 8 bad divers out of 10, you will think no, no crossovers, only complete courses. You also will think nobody should dive a ccr in a cave with only an oc full cave card.
If you see 8 good divers that know what they are doing out of 10, you will think, the crossover is ok as mentioned in standards.
If there are no laws about diving a ccr in caves, you can complaign, you can think they must do a course, etc, but you cannot blame people of doing it without a card. You are no police.
In Europe there is no law, so as instructor you can only advice if people do things outside certification limits. And yes, this can become a problem if an accident happens, as it affects also the divers with a cert who should know how it must be done safe. But you cannot say directly the ones without cert don't know it. That is judging without knowing details. If an accident happens, look at internet, important to judge is the name of the diver, the agency and the certs. All things that people want to know asap. And then the discussion starts. You did not like the diver, so it is for sure the divers fault that the accident happened. You hate the agency or instructor, then it is for sure the agencies fault or instructors fault. But you don't look independent to the case.