Comment by davexunit
There are many layers of capabilities. Unguessable process IDs would be necessary for network capabilities. A sandboxing environment would be necessary for system or process level capabilities. It's still worth having the network security even if process security isn't there. Very few language implementations can provide that level of security.
My point here is merely to make sure that people do not come away from this thread thinking that Erlang has, well, anything like this at all. It isn't an especially insecure language as it lacks most of the really egregious footguns, but it isn't a specially secure one either, with any sort of "capabilities" or anything else.