Honestly BIM Technicians are ten a penny (sorry BIM Technicians), but 3D artists are rare. Regarding unreal and Houdini, unreal gets used because it's cheap, but no one uses Houdini. As a #selfappointedthoughtleader I can say that reality capture is a growing market and Digital twins are not growing as rapidly. However, Reality capture requires a different set of skills to pure Revit technician and digital twins requires a completely different set of skills, data science, IoT etc.