He doesn't — can't? — get into the whole Thanos thing and changing their timeline to make everyone come back, but when he thinks about it, it's not at odds with what Bart's saying. The Avengers had only had to course correct five years, not a thousand. Movies about time travel always said that one tiny thing, no matter how far back, could change the whole future. But it makes sense that the reality of it would be different.

"It's weird meeting another version of yourself. I mean, I didn't think the multiverse was a real thing until, like, a few weeks ago? Or a few weeks before I got here, anyway."

Wait, hold on.

"You have an evil clone? Your world sounds nuts!" As if being snapped out of existence for five years was less nuts.