You must understand that there is more than one path to the top of the mountain. Miyamoto Musashi
So many people in this world find something that works for them, and then think that they know what's best for everyone else. This happens a lot in the martial arts world with arguments over style, techniques, instruction, etc. Martial artists like to argue about who is legitimate and who is not, like they are the ultimate judge of everyone else's training, skills or abilities.
The fact is, not every style of martial arts works for every person. Not every technique is a good fit for every martial artist. Different people have different body types, different injuries, different weakness, and different issues. Just because a martial art works for you, that doesn't mean it is best for everyone.
We can see this same attitude in pretty much everything from health recommendations to religion, and from weight loss to financial decisions. You must remember, as Musashi stated, there is more than one path to the top of the mountain. Not everyone must take the same path to reach their goals.
It doesn't matter how great anything is for someone else; what works for you is what matters in your life. It may work well monk in a monastery to meditate for 4-5 hours a day, but that most likely won't work well for you if you are living in the U.S., holding down a job, and working to provide for your family. Just because it works for the monk, that doesn't mean is is a good fit for you.
Find the right path for you, whether it is in your martial arts training or in any other area of your life. Quit focusing on what everyone else does, and start focusing on what works for you. And stop allowing the opinions of others sway your decisions about your life. You don't need anyone's permission to live your life as you see fit or to do what is best for you.
If you can't throw a roundhouse kick because of hip problems, it is silly to think that you will be able to use a roundhouse kick to defend yourself if you are attacked on the streets. If it doesn't work for you, find something that does. Don't let some pompous, self-proclaimed "Grandmaster" tell you that you are not a martial artist if you can't do this technique or that technique.
Martial arts training is about self-defense and self-improvement, not about being a clone of some self-important, arrogant martial arts "Grandmaster." If any instructor demands that you do everything exactly as he does, he is not intelligent enough to continue to train with, nor does he understand the premise of the fighting arts. Perfect what works for you, and walk away from what doesn't.
You are not on this earth to fit into anyone else's expectations of how you should do things or what you should be. You are here to live your life, your way, and the be best YOU that you can be. Quit trying to walk in the footsteps of other people, and find the path that works for you. I promise you, there is more than one path to the top of the mountain. Warrior up!