I think one of the camps on difference between "internal" and "external" might be a camp I can understand.
External= Improving physicality, more physical power
Internal= Improving efficiency, better use of existing physical power
Is this a general idea that people hold as the difference between "internal" and "external" martial arts?
If so, then do people believe that modern athletics does not seek to train more efficient movements? Is it a generally held belief that athletes are people who only seek to become physically stronger, faster, conditioned, agile etc. but do not practice technique? Is it a belief that athletes spend most of their time lifting weights and doing drills only to improve physicality, but there is no "rewiring" done, and they do not seek to improve their movements?
I think you could characterize it that way if you assume that the there is only one way to efficiently move and neither internal nor external movement is inherently different. The problem I see with that is that what is considered efficent for external movement, is not always considered efficent for internal movement because they move fundamentally differently. That is to say, there can be at least two ways of efficent movement, both of which have their tradeoffs.
I think you have to differentiate technique from principle. Technique generally refers to one specific movement for a particular situation, such as a particular waza. Principle is generally how you power any particular waza. This is why I tend to state that a throw is the same as a kick, as a cut as a punch. It is a different focus in terms of how you practice.