Multithreaded programming is still one of the most problematic activities even for senior programmers

I agree wholeheartedly. FWIW I've found higher level abstractions built into the language itself, such as atoms and refs in Clojure, go a long way toward mitigating the problem once and for all. This gives you an actual harpoon to hunt Amdahl's* Great White Whale of Parallelism. Instead of a toothpick (C++) or a pocket knife (Java) to do it.

The trouble is we need to stop hunting whales if we're going to move the needle in a permanent and significant way...

* https://en.wikipedia.org/wiki/Amdahl%27s_law