Several problems, all the hikers' fault:

First, they ran away from the bear. (Not in the above cited article, but in many others.) You never run from a charging bear or any other charging animal. To a predator, if it runs, it's dinner. If they had stood their ground, more than likely it would have been a bluff charge--the bear would have come close and then stopped and backed off. The wife did do the right thing when the bear caught up to her by playing dead.

Second, they definitely should have been carrying bear spray. A good squirt would likely have done the job. That's why the park staff recommend it!

Third, you don't hike in grizz country without making noise as you go, particularly in an area where you can't see what's ahead. Once they rounded the corner and surprised momma bear at close range, the results were normal and natural bear behavior, which is why momma bear is still alive.

The only grizz I ever saw was in Yellowstone along the road. People were walking right up to it to take pictures. I pity the park personnel having to try to protect people from their own stupidity. They certainly spend a lot of time and money (our money!) trying to educate the tourists about the dangers of wildlife.