As you have noticed, no matter how hard a Taekwondo class trains, it is not as hard as a traditional karate class trains. Today, Taekwondo is a business. To keep customers happy and coming back, you have to give them what they want. What they want is the prestige of earning a black belt, but they want to earn it with as little time and effort as possible. No matter what people say, people have more money than they have ever had in the past, and, to get the money, they are working longer hours than in the past. So, they are willing to pay more to get something quicker and easier—Taekwondo lets them do it this way.
I have found that beliefs in ki, meditation, and other supernatural things are just that—beliefs. All these things exist without being religious beliefs. Professional athletes use these same techniques in one form or another without any religious connotations. People tend to attracted to the strange and different. They see a race car driver sitting alone and concentrating before a race as clearing his mind for the race, while the see the martial artist doing the same thing before a fight as meditating to concentrate his ki. The later seems more exotic than the former.
I too have read, heard, and even been taught that one does not understand a form until it has been performed 1000 times or that it takes a lifetime to understand a punch. If one says it took him a lifetime to understand a low block, the person is either slow or has alterative motives behind the statement, such as self aggrandizement. The later is usually the case. People become world champions at many sports while in their teens or twenties’ it did not take them a lifetime to perfect their sports or understand their intricacies.