My reference to “fast” was in the context of creating a new process due to the OP post talking about how long fork/etc can take. Not in reference to executing code itself.
In that sense it’s fast in the same way e.g. coroutines(/goroutines) are fast: it’s just the erlang scheduler performing some allocation (possibly from a freelist) and initialisation. Avoiding the kernel having to set things up and the related context switches makes for much better performances.
