And now with say 24 hours and less you get the same card OW and you have learned next to nothing as compared to what the original content was. Why so they can sell more classes under different names. with no consumer benificial additional environment advantage to taking further training. More or less it is either basic OW or tech. And to do tech you are made to buy more classes to get there because of what you don't know and was never taught in the 24 hour OW class..
But new divers are not required to take the additional classes. Your point would be valid if the agencies required several classes to become certified, so students were required to take those classes to achieve the same certification from the old days (that you allude to.) But new divers are not required to take those extra classes. In fact, most students take only the first basic OW class.
Do they learn as much in their OW course as you did in the "old days"? Probably not. But... do they
need to learn everything that you did?
Probably not.
So why did the cert agencies change? Because over the years they learned that people don't need everything that's included in the old OW course (i.e. up to divemaster training) just to go diving. The purpose of the change was not to sell more classes (because they don't really... the majority of divers take only the OW class. And yeah, I know I already said that above.) It was to get more people diving. So the modern OW course was designed to just give people what they need to know to be able to just go diving.
For example, in your old OW course you might have learned some rescue techniques. Why don't they teach that in the modern OW course? It's not necessary. Certainly rescue skills can be useful... but knowing how to rescue someone is not truly necessary to be a scuba diver. Case in point: I took the Rescue class many years ago. And I took the DM course, in which we repeated the skills from the Rescue course. And then I did the IDC... in which we repeated the skills from the Rescue course. By the time I became an instructor, my CD decided I was good enough at rescuing people to
teach people how to rescue people.
And in all my years of diving I have rescued... zero people. (Oh wait, important clarification: I have had zero opportunity to rescue people.)
Did the Rescue training make me a better diver? Absolutely. It taught me skills that can be useful, skills that perhaps allow me to recognize how to
prevent a situation that could create a "rescue opportunity".
But the simple fact is that the current OW course provides the knowledge and skills a new diver needs on which to build their experience to become a safe and competent diver.
There is a reason that training curriculum evolves. There is also a reason people that did things the "old way" will continue to complain that the "old way" is better and the "new way" is worse. What will not change is that the most important elements of any training are how dedicated the instructor is to the quality of their instruction, and how dedicated the student is to understanding and applying the training properly.