Analysis of real software that has looked for the maximum theoretical implicit concurrency has found that software to have its implicit concurrency level top out very quickly, often not even making it up to 2x. You don't hear about this today not because nobody has tried it, but because it's been tried and it hasn't been found worth the bother. Amdahl's law is a real jerk sometimes.

If you want concurrent code, you're going to have to write it with an awareness of concurrency issues. There are things that languages can do to make it easier, but in terms of doing it automatically even that hasn't had a great track record. Fortress [1] took a good run at it, but ultimately didn't seem to get that far, at least relative to their ambitions.

Personally I suspect that while Haskell may not be that language today, and may not be that language ever necessarily, that the "magically concurrent" language of the future is going to end up looking a lot like Haskell, in particular, with the ability and need to consider the mathematical properties of your code for things like associativity and commutativity. It's going to take a pretty major sea change in a whole lot of attitudes before "the youngsters" are just casually reeling off group theory names while the "old fogies" are stuck going "What's a monoid again?" Not impossible, but hard to imagine how we get to there from here.

[1]: https://en.wikipedia.org/wiki/Fortress_(programming_language...