This paper analyzes the economic and operational benefits of moving from proprietary vertical cloud silos to a unified horizontal telco cloud architecture. Traditional silo-based deployments in mobile core, IMS, and IT environments create vendor lock-in, low server utilization, high professional services costs, and operational complexity. Using a five-year total cost of ownership (TCO) model, the study compares silo architectures with a horizontal model based on VMware Telco Cloud Platform and VMware Cloud Foundation. The results show that infrastructure consolidation, shared resource pooling, and end-to-end automation significantly reduce server counts, labor costs, power consumption, and integration expenses, resulting in cumulative five-year TCO savings of 40.8%.