FE Hoppy
The theory is perfectly sound, but the application to a given situation might be inappropriate. The universe in general seems to run on using the minimum effort to achieve the maximum effect. Entropy will ultimately rule, but in the meantime efficiency and conservation of energy is what keeps everything going. That being the case, the most efficient design for a given circumstance will ultimately win out until the circumstances change and a better design is called for.
The laws of physics dictate that there is a rapidly diminishing return as the size of supersonic aircraft increase. It becomes too hard or too enviornmentally damaging to displace the air for very large craft. This is less of a problem at subsonic speeds, where even quite large increases in aircraft size are not accompanied by disproportionately large increases in drag or wing loading. In fact overall efficiency can be improved in many cases.
Geopolitical factors are just one of many things that need to be taken into account with analysis of this kind and it is right for you to point out that not everything is necessarily measurable as a physical quantity.