I was a kid in the 70s, and while reel-to-reel was on its way out by then, I still remember seeing them as parts of my friends' parents' hi-fi setups. They were beautiful pieces of equipment.
The machines were, and still are, beautiful. Good ones were usually pretty expensive and represented the state of the art in their day, like a flagship smartphone or laptop computer now. Even obsolete, you can see the quality and the beauty.
But the real problem is the recordings. It's not just stuff like home recordings off the radio, it's original masters of albums. The Beatles early BBC stuff was recorded on Ferrograph machines (I love that name, think about what it means). God only knows what the tape formulation was; iron oxide, for sure, but what were the binders?
Most Slashdotters will be familiar with cassettes moving the tape at 1-7/8 inches per second. 7-1/2 inches per second was common in home audio. 15 inches per second in professional/studio audio use was fairly slow! At those speeds, as the tape plays, the oxide breaks free from the binder and blocks the head gap pretty quickly. Slowing down the tape and digitally replaying it faster might help, but it doesn't change the fact that A Day In The Life is a lot of tape at 15IPS - and a it's distance, not speed, that really clogs the head gaps. 5 minutes and 35 seconds is 418 feet of tape at 15IPS. No matter how quickly or slowly you play it, you could tie one end to the balcony railing of a 42nd floor apartment and the reel would still be unwinding when it hits the sidewalk below. And that's A Day In The Life, not something crazy long!
Now you add video recording with high-velocity spinning video heads to tape with flaky backing, and you're going to have a real problem playing this media down the road. You need the machine, stable tape, and someone who actually knows how to do it.
With commercial video formats far before VHS, there aren't many people alive who know how to maintain and run an Ampex Quad machine, for example. And with that, it's the end of countless hours of video recordings since the dawn of VTRs in the 1950s - Dr. Who, Coronation Street, WKRP. Life-altering news events, triumphs and tragedies. This is akin to losing our literary history because no one knows how to read.