The proliferation of the Industrial Internet of Things (IIoT) has transformed energy distribution infrastructures through the deployment of smart metering networks, enhancing operational efficiency while concurrently expanding the attack surface for sophisticated cyber threats. In response, a wide range of Machine Learning (ML)–based Intrusion Detection and Prevention Systems (IDPS) have been proposed to safeguard these networks. In this study, a systematic review and comparative analysis were conducted across seven representative implementations targeting the Internet of Things (IoT), IIoT, fog computing, and smart metering contexts. Detection accuracies reported in these studies range from 90.00% to 99.95%, with models spanning clustering algorithms, Support Vector Machine (SVM), and Deep Neural Network (DNN) architectures. It was observed that hybrid Deep Learning (DL) models, particularly those combining the Convolutional Neural Network and the Long Short-Term Memory (CNN-LSTM), achieved the highest detection accuracy (99.95%), whereas unsupervised approaches such as K-means clustering yielded comparatively lower performance (93.33%). Datasets utilized included NSL-KDD, CICIDS2017, and proprietary smart metering traces. Despite notable classification accuracy, critical evaluation metrics—such as False Positive Rate (FPR), inference latency, and computational resource consumption—were frequently underreported or omitted, thereby impeding real-world applicability, especially in edge computing environments with limited resources. To address this deficiency, a unified benchmarking framework was proposed, incorporating precision-recall analysis, latency profiling, and memory usage evaluation. Furthermore, strategic directions for future research were outlined, including the integration of federated learning to preserve data privacy and the development of lightweight hybrid models tailored for edge deployment. This review provides a data-driven foundation for the design of scalable, resource-efficient, and privacy-preserving IDPS solutions within next-generation IIoT smart metering systems.