Errrrm, if you ever look at the AVR C library that Arduino was based off of, you would probably not be so quick to say that it isn't a language issue. Not having to know the weird unpronounceable mnemonic for a certain register as well as the specific bit in that register that you set in order to trigger the ADC is a huge plus. Greater abstraction is always welcome if the hardware can handle it.

Although I agree with you that Arduino C is simple enough for most microcontroller programs and Javascript is a bit overkill.