I'm not saying compilers shouldn't optimize, they just shouldn't try to be clever. Some things can be expected to be done by most any compiler, many things are extremely compiler-specific and only work under very specific circumstances.
Clearly that is not what you mean and is not a good thing. Perhaps optimizing compilers put you outside of your comfort zone because you think they force you to learn and keep up to date.
You can do that or you can stick to writing idiomatic code that uses the std library for a given compiler. Doing just this tends to produce extremely good results. I often outdo others near just with this when they are dropping to assembly or doing silly workarounds because they know something is slow. Profiling and timing are required to pick up the rest of the performance, and presuming otherwise is silly. No special knowledge of the machine or compiler is required, just a knowledge of when and how to optimize and when and how to write idiomatically.