Old Release Of Erlang On Apple Silicon

Hi all,

When I attempt to install Erlang 21 on a new Apple Silicon chip I get
this message:

onorio.catenacci$ brew install erlang@21

erlang@21: The x86_64 architecture is required for this software.

Error: erlang@21: An unsatisfied requirement failed this build.

I found this:
https://stackoverflow.com/a/67098973/2820

But it doesn't seem to do the trick.  When I attempt to run it I get this
message:

onorio.catenacci$ arch -x86_64 brew install erlang@21

Error: Cannot install under Rosetta 2 in ARM default prefix (/opt/homebrew)!

To rerun under ARM use:

    arch -arm64 brew install ...

To install under x86_64, install Homebrew into /usr/local.

Has anyone gotten Homebrew/Rosetta working with an older version of
Erlang?  I realize it's still pretty new so I'm not expecting it to work
turnkey but I was hoping others might have seen this issue and figured out
a fix.

I'm looking for stuff on Homebrew and Rosetta as well but it seemed that
some of the folks here may have run across this one too so I figured there
was no harm in asking.

-- 
Onorio