Compilers aren't different from pretty much every other kind of software, for which it's generally painfully obvious that two programs that target the same data _format_ will not necessarily output the exact same _data_, especially when they have wildly differing end goals.

I don't think every article discussing benchmarks has to restate that the differences between programming languages are not just syntactical to be informative.

I'm not sure I follow. What I meant is that a benchmark over a specific task is not really informative without a comparison of why it is slower in some languages compare to other.