Assessing smart grid reliability, considering both cyber and physical components, typically involves a mapping step, escalating complexity and computational overhead. This paper presents a pioneering mapping approach that redefines the fundamental paradigm of smart grid reliability assessment. By leveraging a defined interconnection matrix, the method optimizes computational efficiency, curtailing the array of potential system states. Evaluation employing key performance metrics - Loss of Load Probability (LOLP) and Expected Energy Not Supplied (EENS) - quantitatively demonstrates the superiority of our approach. Also, we explore the ramifications of integrating a dynamic thermal rating (DTR) in the process of reliability assessment, augmenting component safety through permissible enhancements in their ratings. Results underscore a notable reduction in total system states, from 221 to 214 for the bus topology and from 222 to 216 for the ring topology. Moreover, the analysis reveal substantial enhancements (Up to 43.58% ) in reliability indices upon consideration of the DTR system.