From anyone else, the Once-ler might be annoyed or hurt by the jab. But...she's right. She knows his story already, and he's been in and out of that spiral for days now, ever since the event began. He would just fall back into it if she didn't drag him out of it. She's one of the only people who actually can empathize with him, which helps them avoid an additional twenty minutes of him trying to explain how no, he's actually a terrible person. She knows that and he knows a good chunk of her dark past too, so they can just skip all that.

"I haven't," he says, but then when he realizes how sad it sounds he amends it. "I mean...the tent's fully stocked with a kitchen and all my stuff from when this was actually my life, so it's not like I needed to?"

In other words, yes he's been a hermit but at least he has food to eat and a bed to sleep in and a sunny day on loop, so this could be significantly more pathetic than it is. The last bit surprises him though, and he raises his eyebrows.

"A barn? Really? I never would have guessed," he says. Then, a friendly laugh. "With all due respect, I would've assumed you'd never stepped into a barn in your life."

She is/was royalty, after all. Then again, his world didn't really have real royals, so what would he know?