Here is the truth of the matter.
There is a huge amount of overlap, in terms of what techniques are found in one system to the next. They may not be exact or identical, but they are similar or variants. Punches,kicks, elbows, knees, joint locks and manipulations, throws, takedowns, immobilizations, grapplings, breaks, rips, pokes, etc. lots of systems have lots of these, in some shape or other. Very few techniques are found exclusively in only one system. That is a rarity.
It is a mistake to think this or that technique is from this or that system. It is also a mistake to think it is not.
A martial system really defines a training methodology, more than a body of techniques. I think many people focus on the techniques, and fail to recognize the training methodology underneath. And so we have arguments over whether Jon Jones is doing Kung fu or something else when he throws a certain kick. What he is doing with that kick depends on the context in which he learned it. But someone else doing the same, or a variant on the same kick, is doing it from whatever context he learned it.
People need to stop thinking about a martial system as techniques, and start recognizing it as the methodology used to learn and develop and train and practice skill with those techniques. It is mostly a shared body of techniques. But the methodology can be quite different from one system to another. That is where the real difference lies.
Once you can recognize that, most debates like this one become pretty meaningless.