An email address is no Vorladungsfähige Adresse. You can't sue that, you can't send a Gerichtsvollzieher to it, and you can't seize the owners assets with it.

If I want to send an Abmahnung to a website owner, because they publicly defame me — as has happened before — then I need something stronger than an email address. Or I need to invoke the right to be forgotten, but I don't want to do so, I prefer having a way to eliminate the source.

You are talking about an Impressum. No need for that info in the whois.

The topic was Impressum. The user starting this subthread complained about Impressum.