You give a great example of Euler's 1st problem (https://projecteuler.net/problem=1) but if someone wasn't given the context of the problem, or even if they were are unfamiliar with the syntax you used, they would not call you solution 'simple'.
That being said transfer of knowledge is a key component when reading. Going to your point about the decimal system (which I believe you were talking about the arabic numberals (https://en.wikipedia.org/wiki/Arabic_numerals)). Sure it is faster and shorter to use than Roman Numerals, but then again the knowledge transfer that you could do with Arabaric numerals is much greater than Roman.
I would say for programming languages, ever time we, programmers, innovate on one we are trying to make a process simpliar to the user (I believe 'abstraction' would be an appropriate word to use).