In my particular case, I had gone through the course and watched the videos and got everything working for development. Then, I had to redirect my attention for several months. When I finally got back to being able to continue, I had forgotten quite a few details and had hoped to be able to quickly refresh my memory. I have managed to noodle things out, but it would have really been nice to be able to review. I guess I just assumed that it would be available (perhaps as an archive) and so I didn't really bother taking notes.

However, as to changing versions and such of Postman, I am not really sure that is as strong an argument as you might think. I could be wrong, but I suspect most people who were using the course were developers at some level. I would like to think that we are not as susceptible for "shiny shock" in terms of changes in appearance. As far as features are concerned, I just updated to 11.57.5 and haven't found any features that have become premium. That said, I primarily use Postman as a prototyping tool and write software/scripts for actual production use. So, I really don't know about the changes in finite resource limits (like "Calls to Postman API/month) that are part of the free version.

If you are considering rebooting the course, I would be very interested, still. Also, whenever I have done training using tools that I don't control, I usually steer to the center and not include any whiz-bang that is tool specific or might be considered a limited time trial premium.