As XR wearables and automotive cockpits move beyond keyboards, real-time speech translation, emotion and fatigue detection, voice biometrics, and audiovisual fusion are emerging as essential interface layers. Combined with advances in agentic AI, multimodal LLMs, synthetic data, digital twins, and edge/tiny-ML, these innovations enable low-latency, on-device intelligence. Driven by scaling laws, compute costs, and regulation, the field is rapidly evolving toward autonomous, context-aware systems with built-in safety and alignment.