LingVM is an Erlang VM that runs directly on Xen
medium.com
medium.com
Even with RumpRun on true bare metal, should that be called "Bare Metal Erlang"? It's not like the erlang code manages the raw memory, contains a driver for the hard disk controller etc.
Clearly there are fewer layers between the erlang code and the bare metal compared to a traditional OS, but still plenty and they do quite a lot of work.
On a related note: there is also the nerves project for embedded Erlang/Elixir - http://nerves-project.org/