Also MultiLisp, QLisp, *Lisp, and others. Parallel lisps are not a new concept, though they were often written with specific machines in mind (*Lisp for instance).
It's not about them being a new concept. Do we have Erlang actors or Golang goroutines there? Are they fully safe like Erlang's actors or Rust's futures would be (provided you don't use escape hatches)?
If not, they remain toys.