I read through the article and I am feeling lost as to why they couldn't actually retool their production pipeline for 4K native. 40 cameras sure does sound like a lot, but I am watching guys on youtube shoot 4x the pixels and manage their workflows around the massive volumes of data (apparently) without issues.

Is it the broadcast equipment itself blocking the production pipeline from an upgrade? I would be very interested to hear from a broadcast industry pro where the actual technical constraint is (bandwidth, storage, compute, hardware, etc.). I feel like financing this wouldn't be a problem for the NFL+Fox.

The short answer: The live broadcast switching/transport industry has been slower to adapt to 4K HDR than other industries, primarily because there is no live broadcast (ie. cable, satellite, over-the-air) support for 4K or HDR.

YouTubers can do 4K because modern desktops (and some laptops) have h.265 decoding/encoding acceleration, and they're typically only dealing with 2 content streams on a single timeline. An NFL broadcast is a living nightmare compared to that.