It is the standard in healthcare though. The world is using it to exchange data for both payor and clinical. The US has mandated the use of it for healthcare. Its built into Apple and Samsung Health apps. You can get your entire FHIR chart via mychart (epic) instances (along with many other EHR systems). And yet I'm having to prove out why we shouldnt use custom structured ORM models to translate in/back because many have grown so accustomed to it.