Multi-cloud deployment has become the operational norm for a growing majority of enterprise engineering organizations, driven by a combination of regulatory requirements, vendor risk management, geographic distribution, and workload-specific capability matching. The observability challenge this creates is substantial and underexamined: each cloud provider generates telemetry in proprietary formats, at different granularities, with different semantic conventions, making unified monitoring of cross-cloud systems genuinely difficult rather than merely inconvenient. This paper examines the observability strategies employed by thirteen engineering organizations operating active multi-cloud DevOps deployments, studied over an eighteen-month period from January 2023 through June 2024. We analyze telemetry aggregation architectures, the adoption and impact of OpenTelemetry as a vendor-neutral instrumentation standard, alerting consistency challenges, and the operational cost of maintaining fragmented versus unified observability stacks. Results demonstrate that organizations operating unified observability architectures reduce mean time to incident diagnosis by an average of 63% compared to organizations managing provider-native tooling in parallel, and that OpenTelemetry adoption is the strongest single predictor of observability maturity.