Measurement frameworks were born national. A country has a broadcaster, a panel, a time zone, and a regulator, and the whole apparatus assumes an audience that lives inside those borders and watches at roughly the same time. That assumption held when culture was delivered through national pipes. It does not hold anymore.

A modern cultural event does not respect the container. A match, a finale, a song: it spills across borders, across a dozen platforms, and across every time zone at once. The moment is simultaneously live in one place, streamed later in another, clipped and re-shared everywhere, and consumed on screens no national panel was built to see.

• Borders: the audience is planetary, but the measurement is licensed and counted country by country.
• Platforms: one event fragments across broadcast, streaming, and social, each with its own incompatible counter.
• Time zones: consumption is asynchronous, so "how many watched" has no single moment to be measured at.

The deep problem is that the unit itself breaks. "An audience" quietly assumes a bounded group sharing a moment. When the group is global and the moment is smeared across days and platforms, there is no clean thing left to count. You can sum national numbers, but the sum double-counts, under-counts, and misses the re-shares entirely.

You cannot add up national audiences and call it a global one. The event was never national; only the ruler was.

So the honest answer is that we do not yet have a good instrument for planetary, asynchronous attention. The frameworks we use were engineered for a world where culture stayed home. Until the unit of measurement is rebuilt for events that do not, every "global audience" figure is a stitched-together estimate wearing the confidence of a count.