This paper doesn't say ANYTHING about _capacity_ for critical thinking, and by using the words "critical thinking" yes it makes it sound like "more is better", but look at what they're actually doing. What they're measuring I would much more call "oversight".

If I want to know when Obama was born, and check wikipedia and believe what it says, by their measure I am practicing less critical thinking than if I found independent verification. Independent verification is the main way they measured critical thinking. They are NOT measuring that I thought about how much I could trust the result, and decided that yes I could.

And, well, yes, they're right. But for most purposes, wikipedia is pretty credible for something like that, and it's just a waste of time to follow up on it. What's important is that my calibration is correct.

I'm not even saying I disagree with the idea that there is likely a problem here, with people offloading thinking. But I'm thinking critically about this particular study, which seems totally useless.

Well, I could argue that by inviting a comparison between trusting a single fact from Wikipedia and trusting arbitrary generated output, you are practicing less critical thinking than you otherwise might.

The example's not relevant; the two things are not analogous. Moreover your point only works if one accepts your conclusion that:

    Independent verification is the main way they measured critical thinking

But they also reported assessing things about the content, like style/personality, logical soundness, relevance to a topic, or suitability for a specific purpose.

Studies don't need to justify themselves with concrete conclusions; gathering the data for future use is a fine goal.