According to the 2020 report on Property constraints (T244043):
The "Property scope" constraint type is the second least known constraint type and one of the constraint types with the least descriptive names according to active editors. Its purpose can easily be confused with those of "type" and "allowed entity types" constraint types.
| Status | Subtype | Assigned | Task | ||
|---|---|---|---|---|---|
| Open | None | T244043 suggestions and possible decisions from the 2020 report on Property constraints | |||
| Open | None | T244057 Consider giving the "Property scope" constraint type a better name |
I haven't been able to find a sufficiently descriptive name apart from those that list the three possible "scopes", something like "main-value/qualifier/reference constraint type", which is surely not the best name ever.
<joke>
Another option is that this constraint type becomes a default Wikibase feature consisting of checkboxes displayed on Property pages that enable the use of a Property for the main value, as a qualifier or in a reference.
This is one of only two types whose constraints have the mandatory severity level (1,221, 78%) more often than the normal severity level (349, 22%). Consistently, it has no constraints with the suggestion level and is one of the constraint types with the fewest exceptions. Widely applicable constraint types without exceptions, with a high proportion of mandatory constraints and with a clear and controlled set of parameters should be considered good candidates for becoming default Wikibase features.
</joke>