One thing that Wikidata does well at the moment is adding external ids for many items do to external databases. As far as I understand StrepHit paid in the past for data annotation and it's developer focused on getting the data import from specific websites and properties to work.
This might not be a scalable way to solve the problem given that we add many new authority control properties every week. This means that many properties that are in the long tail currently don't get a benefit from StrepHit.
The long tail is also a place where there's a higher chance that we develop data that Wikipedia doesn't already have than at a domain like football that's already well covered.