I think there are situations (maybe sneak attack) that call for a create hostile to your target rather than an ally of you.

Is that intentional so a third party can be either your ally or only the enemy of your enemy?

— Viktor Bengtsson (@ViktorEGB) November 12, 2018

Yes, that's intentional.

— Jeremy Crawford (@JeremyECrawford) November 12, 2018