It has.
"The Boss Baby" has been announced to be coming out to BluRay 3D. Also, a sequel has been announced, which is the most unbelievable thing I'll likely type this week. So now "Trolls" lack of a proper 3D release is looking more like an anomaly. Will we get a 3D re-release? Unlikely. Disney tried that with "Star Wars: The Force Awakens," and it didn't really do anything other than piss off fans of the movie, so I think most studios are under the impression that they either need to release it on day one or not release it at all. Given the choice I would rather get these eventually than never, but why we even need to worry about separate releases is still something I'm grappling with. Either way, I will be picking up "The Boss Baby" when it gets a 3D release. Yeah, it's no where near my favorite movie, but I do generally buy DreamWorks movies, so this will just be something to add to the collection while still supporting the format.