I've done some JKD over the past 8 years, and I've learned that what makes it a "thing" is focussing on what you're trying to achieve; learning to fight. I took a very unorthodox concept based Kenpo class for 8 years prior, and it's very much the same in it's methodology, just taking it's components from slightly different places.
The difference between 'Mixed' martial arts and 'jkd' seems to be mixing things up makes diversity without a necessary common element, and concept based 'systems' often have an underlying foundation in similarity. That similarity helps to relate one thing to another and concequently things are theoretically learned both faster and deeper, using limitation as a way of freeing oneself from limitation. Using a crutch only until you can walk.
I think all 'arts' or orthodoxies in lifestarted off with this flavour of original freedom. Don't get bound by 'style' since that's just someone else's interpretation of what they learned and how they teach the lessons they've cultivated over the years. Too many generations of that and you end up with a lot of rules and rituals, but no understanding whatsoever.
That attitude of honest research, practice, and the transformation of knowledge into wisdom through the development of skill (practice and experimentation, constant improvement) should be in place in every person, like it is with most children, regardless of the name you've chosen for your person understanding of the way things are.
I think, whatever Bruce is credited for having said is made famous and marketed outside of it's relevance, and like him, I think each individual must walk the path to understanding themselves, for and by themselves.