They are already disallowed.

In Appendix A "Schema for Schema Documents (Structures) (normative)":

  <xs:element name="openContent" id="openContent">
    ...
    <xs:complexType>
      <xs:complexContent>
        <xs:extension base="xs:annotated">
          <xs:sequence>
            <xs:element name="any" minOccurs="0" type="xs:wildcard"/>
          </xs:sequence>

Here type "wildcard" doesn't allow min/maxOccurs. To allow them on normal wildcards:

  <xs:element name="any" id="any">
    ...
    <xs:complexType>
      <xs:complexContent>
        <xs:extension base="xs:wildcard">
          <xs:attribute name="notQName" type="xs:qnameList"
                        use="optional"/>
          <xs:attributeGroup ref="xs:occurs"/>

P.S. this also means that "notQName" is not allowed on <any> in open content. I do not recall why that's the case.

Thanks for pointing this out.

Closing as invalid.

IMHO, this seems like something that should be noted in the main body of the recommendation.  At least for minOccurs/maxOccurs, you can see on a careful reading that they would be ignored (if they were allowed).  The notQName attribute is more subtle.

There is an analogous situation at the end of 3.7.2, where the XML representation presented is not precise and attention is called to the implications of the S4S.  That seems like the right approach, as readers will have the expectation that the XML Representation sections are complete - at least, that's been my expectation.

Please consider reopening this one.