Do you have some examples where we explicitly want to say that novalue and somevalue are not allowed? They should theoretically be allowed everywhere.

Quick example: biographical properties like date of birth are known or unknown but they always exist (everybody was born some time somewhere), so novalue doesn't make sense. This constraint could help catch this abuse, as well as somevalue × novalue confusions. I realize now this could be implemented together with T183092: Make an obvious way of blacklisting a value for a property.

Hmmm date of birth might make sense as no-value for fictional or religious entities. https://query.wikidata.org/#SELECT%20%3Fitem%20%3FitemLabel%20%3FitemDescription%20WHERE%20%7B%0A%20%20%3Fitem%20a%20wdno%3AP569.%0A%20%20MINUS%20%7B%20%3Fitem%20wikibase%3Arank%20%3Frank.%20%7D%20%23%20remove%20statements%20%28%60rdf%3Atype%20wikibase%3AStatement%60%20is%20munged%20away%20in%20WDQS%29%0A%20%20SERVICE%20wikibase%3Alabel%20%7B%20bd%3AserviceParam%20wikibase%3Alanguage%20%22%5BAUTO_LANGUAGE%5D%2Cen%22.%20%7D%0A%7D%0ALIMIT%201000 has some bad data but also some that seems valid.
FWIW I'm not against having this but I am unsure.

This could be possible via T183092: Make an obvious way of blacklisting a value for a property. Is it correct, @Lucas_Werkmeister_WMDE?

Not really, both “one of” and “none of” are only for item values so far, not for other types of values (like time values).