The HN rule is that anything can be posted if it is accessible to everyone, including via a paywall workaround if it has a paywall that is porous.

The community has converged on this being the least-worst approach after wrestling with the issue for well over a decade, and it's sufficient to helpfully post the archive link without a snarky editorial comment :)

If I had my 'druthers designing a new link-share/comment system, the visibility (and mirrors or excerpts) for the target would be part of the model.

In other words, an icon showing whatever-wall status, submitter can add an alternate link, etc.