Issue SPF useless when Plesk Email Security installed?

[cs50935]

Server operating system version

Ubuntu 20.04

Plesk version and microupdate number

Obsidian 18.0.43

I have SPF active on my Plesk installation and addesd the free Version of Plesk email Security. Since then the header of ALL emails say:

"Received-Spf: pass (XXXXX.de: localhost is always allowed.) client-ip=127.0.0.1; envelope-from=newcclasse@t-online.de; helo=XXXXX.de;"

When I look further I see the lines:

Received: from XXXXXX.de (localhost.localdomain [127.0.0.1]) by XXXXXX.de (Postfix) with ESMTP id AA8481CA099F for <name@domain.de>; Tue, 24 May 2022 18:56:35 +0200 (CEST)

Received: from XXXXXX.de ([127.0.0.1]) by XXXXXX.de (XXXXXX.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id VTZ39yHSBtdQ for <name@domain.de>; Tue, 24 May 2022´
18:56:33 +0200 (CEST)

Received: from a07c35de5bd2f8f744eea70cea8ea4a41cacda (unknown [6x.xxx.xx7.65]) by XXXXXX.de (Postfix) with ESMTPS id A0FE01CA0673 for <name@domain.de>; Tue, 24 May 2022 18:56:09 +0200 (CEST)

So for me it seems that the "routing" of all mails through Amavisd which came with plesk Email Security leads to the issue, that the following SPF-Check always thinks that the Email comes from localhost. That would make SPF useless if this is really fact. Or am i Thinking wrong?