There are no details in the article.
Literally nothing.
Or maybe there is a paywall, and all I can read is a summary?

Oregon law requires fall protection for more than 6 feet.

I mean, they had fall protection. Just not adequate fall protection.

Fall protection is also super subjective (unless it’s a legal term in the US?).
Fall protection is suitable access platforms and handrails to prevent falls.
I imagine “fall protection” - as the article means - is more about reducing the injuries of falling in a wide open space. I think they mean a fall-arrester. It stops your fall, unless something else does.
It doesn’t protect you from falling into something.

Something like the Petzl Absorbica is a fall arrester. It’s essentially a “safety cord” sewed together with special thread in a tiny bag. If you actually fall on it, the stitching un-stitches in a way that arrests your fall without breaking your back - but it isn’t pleasant. They are a one-time-fall, but better than the one-time-use of living.
You still fall, but it’s safer that hitting the deck.

They are pretty short (tech spec says 0.5ft), and they expand to ~6.5 ft when fallen on.
So, imagine you are working 6ft from where you can safely clip on, using a 6ft lanyard to extend the absorbica. That’s not far.
You might think a fall from that is 12 feet. 6 feet from point, plus 6 feet of absorbica.
Or it could be 18 feet. Cause you are clipping onto something that is 6 feet below you using a 6 foot lanyard: 6 feet fall to be level with the point, 6 feet fall for the lanyard to be effective, 6 feet for the absorbica to arrest your fall. This is a “factor 2” fall. It’s brutal.

Fall protection used incorrectly is borderline worse than no fall protection, because it gives you a false sense of confidence - certainly at lower heights.
Same with incorrect fall protection.

There might have been some sort of retractable fall arrester provided (like an auto-belay. A fixed spool thing with a wire rope that attaches to your harness, and after you reach a certain descent speed it kicks in and slows/limits/stops your descent speed).
It might have been suitable and rigged appropriate for the planned work. But the worked wasn’t trained or informed in it’s use, and climbed above the fall arrester - resulting in a factor 2 fall. Like, a “55 foot fall arrester” meaning the fall arrester is capable of being used 55 feet below it. Not that you rig this device in your work environment, clip it to your harness, and you are invulnerable from fall damage within 55 feet of it - you might not even be safe within 10 feet of it. Retractable fall arresters are not designed for factor 2 falls. They are designed to always be above the human

Nobody should have to go through this, and the company is responsible for this.
If they can prove that the employee was trained according to laws/regulations and executed everything according to laws/regulations/design, then the laws/regulations need to be updated or clarified.
If there is any doubt, punish the company and clarify the regs/laws.
Make sure this doesn’t happen again. Health & safety, or OSHA or whatever, is written in blood