remove rdf:plainLiteral from Semantics?

[pfps]

RDF 1.1 Semantics has a mandated L2V for the IRI rdf:plainLiteral, in https://www.w3.org/TR/rdf11-mt/#literals-and-datatypes. The IRI doesn't appear to be in any other 1.1 document, but is defined in https://www.w3.org/TR/rdf-plain-literal.

Should rdf:plainLiteral continue to be in Semantics? It would seem so, as it is in a normative RDF document. But perhaps there is no reason to continue to support this datatype in RDF.

If rdf:plainLiteral continues in Semantics, should it also be in Concepts? Should it be somehow deprecated?

[afs]

It should not be RDF Concepts because RDF Concepts does not have (RDF 1.0) "plain literals".

Support is optional by the "when ... rdf:plainLiteral isrecognized".

RDF processors are not required to recognize any datatype IRIs other than xsd:string, rdf:langString, and rdf:dirLangString but when IRIs listed in Section 5 of [RDF12-CONCEPTS] are recognized, they MUST be interpreted as described there, and when the IRI rdf:PlainLiteral is recognized, it MUST be interpreted to denote the datatype defined in [RDF-PLAIN-LITERAL].

The existence of a normative document means that an alternative interpretation of the datatype IRI is wrong; the existence of the document does not have to be mentioned. c.f. rdf:HTML, rdf:JSON, rdf:XMLLiteral but also xsd:integer etc.