Edit:
It works fine when creating the pipeline via the API and specifying the material type as package:
"attributes": {
"repository": "e567259e-a47a-4c7b-af37-4ffb275bb5f4",
"ref": "13bf5272-0166-4fe5-9f1a-037960965b66"
}
When editing then the pipeline and trying to add a new material the package option also pops up afterwords.
Still the missing option from when creating a new pipeline looks like a bug.