The notation Pass(Ersatz) shows that the Aufenthaltstitel is an identity document.
It is not listed as an acceptable replacement for a passport to enter Germany.
The Schengen acquis also states that a valid travel document together with the residence permit is required:
Article 21: 1. Aliens who hold valid residence permits issued by one of the Contracting Parties may, on the basis of that permit and a valid travel document, move freely for up to three months within the territories of the other Contracting Parties, provided that they fulfil the entry conditions referred to in Article 5(1)(a)...
When the new Entry/Exit System (EES) is introduced, the Schengen Border Code will have to be changed in many parts.
Unfortunately, there has been no hint as to whether a residence permit will be re-classified as a valid travel document within the Schengen Area.
The German word Pass is (legally) not the same a Passport (in German: Reisepass).
It is an identity document that everyone over 15 must in some form have. A Passport is the main form of a Pass.
An ID-Card (Personalausweis) is a Passersatz (Pass replacement) that fulfills the Pass requirement.
An Aufenthaltstitel is, a Passersatz that fulfills the Pass requirement so that it can be used as an identity document for 3rd country nationals.
It is not listed in the §3,4 AufenthV as an acceptable Passersatz to enter Germany: