The growing IoT landscape demands embedded system architectures that balance performance and resource constraints. This study compares ARM Cortex-M, RISC-V, and ESP32 architectures in industrial automation and healthcare applications. Key metrics, including latency, power consumption, and throughput, were evaluated using benchmarks and real-world workloads. Results show ESP32 achieving TCP throughput of 12–15 Mbps and UDP throughput of 35–40 Mbps, ideal for wireless communication. ARM Cortex-M offers versatility, RISC-V excels in energy efficiency, and ESP32 leads in connectivity. These findings guide IoT system architects in selecting hardware tailored to specific requirements, advancing embedded IoT system design.