The article suggests that the remaining crew members will be able to remain within the capsule and wear only their pressure suits. Surviving loss of pressure is what they are designed for, and since none of them will go outside, then they don’t have to wear the outdoor (outhatch) suit.

“Given that Dragon lacks any infrastructure to support actual EVA work at present, the spacewalk would seem to evaluate only the suit, but risk the entire crew doing so! Is this wise?”

The suit needs to be tested as some point. Gemini tested a spacesuit with Ed White. He didn’t have to do any work, just be outside the capsule and determine what needed improvement in the suit while his shipmate remained inside. The Soviets did the same thing, and they found at least one necessary improvement. Keep in mind that the Apollo command module pilot had to go outside to retrieve some film canisters. Also lacking an airlock. It was not too much risk for the rest of the crew.

If the Dragon pressure suits work, how much risk are the rest of the crew taking?

Given that Dragon lacks any infrastructure to support actual EVA work at present, the spacewalk would seem to evaluate only the suit, but risk the entire crew doing so! Is this wise?