Yeah, but advanced languages are also a problem for long-term maintainability.
Remember, Go was developed at Google - jokingly, while waiting for stuff to compile. They deal with tens of millions of lines of C++ written by thousands of engineers with varying skill levels and career paths. The advancedness of C++ did not reduce the compile times or readability of the code. At those scales you can't rely on being familiar with a particular section of code; you need to be able to drop in anywhere and know what's going on, without having to learn which subset of the advanced language they used for that particular feature.
Advanced languages can compile quickly - it depends on the feature set chosen. For example, do-notation is an advanced feature not found in most languages, but it compiles quickly as it is syntactic sugar. Operator overload, on the other hand, might require a solver and thus compile slower. It's not a particularly advanced feature, however. Binary optimization passes do not make the language any more advanced (on the user side), but will slow down compilation. Advanced design and compile-times are pretty orthogonal.
As for maintainability, it's not clear to me that reams of imperative code is easier to maintain than something terse and declarative. In fact, probably the opposite.
