There are a lot of climbs (and canyons) where you have to rap to get where you want to go. But boy, you have to be careful. My wife and I have been climbing for almost 40 years, and we have become much more careful in the last few years.
Surprising amount of detail in the article for a mainstream news outlet:
"Park rangers and search and rescue team members observed that the man’s rope was not long enough to reach the ground on a long rappel. He tied a piece of webbing to the end of the rope, but the Park Service said he appeared to have made a mistake when disconnecting his rappel device to pass the knot joining the rope and webbing."
It's worth noting that anything that makes a process more complicated increases the risk of failure.