Occam's razor: They wanted an short debt-scenario that reads as unexpected and unusual so that people keep reading, as opposed to a depressingly common scenarios which y'all are probably starting to to imagine just fine without further help.

Whats the right metric to consider credit card debt bad, or degrees of badness? When looking at nations, we look at debt compared to GDP. So for individuals, it would be debt compared to income? So someone who makes 20k and has a 10k credit card debt, is in the same bucket at someone making 200k with 100k in credit card debt. But, the 100k in debt person is in more trouble than someone who makes 500k and has 200k in debt.

The WSJ's target audience is high income earners, so it's more about making a story that appeals to them.

Possibly. Though these days, I wouldn't be surprised if the WSJ was A/B testing versions with different opening examples, while showing 99% of their audience the current "max. clickiness" one.