People seem to need to validate their martial arts to feel that they or their art has value and merit, to feel that they can be secure.
The thing is kungfu is such a broad category and depending on the person who trains it and how they train it you will have different levels of skill. These type of topics and debates have gone on for decades on various forums in time.
In the end, it will be a vast thread of different opinions, name calling, arm back quarterbacking in hypothetical scenarios that all involved will come out with an utter time waste debate.
In conclusion, the best advice is to focus more on training and discover for yourself what is true and a training base on which you can make your question a statement of truth.
Same as any martial art it has good and bad practitioners. If people enjoy training it then that's great. Personally Kung fu isn't my thing but I'm not against it. The more martial arts there are the more different people will train and learn different things and that's only a positive thing