[mrkeen]

One of the prerequisites to this is for the mainstream to stop doing things which are incompatible with concurrency.

Mutation (and other effects) makes the order of computations important. If you're writing to and reading from variables, the compiler is not free to move those operations around, or schedule them simultaneously.

And you probably don't want to be rid of all mutation. So what if you separated the mutating from the non-mutating? Well you'd need a sufficiently powerful type system. Likely one without nulls - as they can punch a hole through any type checking.

If you want this stuff in the mainstream, you at least have to get all the nulls and mutation out of the mainstream, which I don't think will happen.

The industry for the most part heeded "goto considered harmful" (1968), but hasn't done so with "the null reference is my billion dollar mistake (2009)". Maybe we just have to wait.