I believe it could have, and OCaml didn't because of some bad predictions by the core team (when asked about better concurrency, the response was along the line

I believe it could have, and OCaml didn't because of some bad predictions by the core team (when asked about better concurrency, the response was along the lines that we'll all have tens of CPUs soon, so better in process support wasn't necessary), and the restrictions of academia (there is little value given to engineering work).