I would like to add some context. There is a very specific need / use case.
There is an operational discourse that has important content and the content will become more important over time. Because of the nature of the ecosystem that uses it, avoiding central points of failure is something we have learned is very important.
With an export today, if you exclude authentication info, it should be possible to publicly publish the full site content but as @pfaffman pointed out, you end up with an irreversible break where users can no longer authenticate and the exported site becomes read-only.
Therefore I think what Leandro needs is a feature in discourse that allows users to login through cryptographic challenges rather than traditional account/password schemes. Then in the export, only include that part of the account - none of the other email, password hashes, etc. In the alternate copy of the site, now users who took advantage of the feature can login and go through an email/standard account recovery procedure.
When doing that full publication, it will be obviously very important not to include any of the traditional account authentication information like emails and password hashes, etc. It’s so important that for any version of discourse with this feature, the sensitive info should be kept in a separate place from the rest of the site data so that it is impossible to accidentally export.
I hope that gives a little more context to chew on.