Sounds similar to the improv skit mantra of "Yes, and...", where any improvisation ("and then I found the cat on the shelf!") must be accepted and built on.
(e.g. "Oh BooBoo, how did you get on the shelf you silly cat?")
If an actor instead said "No, the cat wasn't on the shelf, the cat wasn't even in the room" the skit ends awkwardly.
“Yes and” doesn’t always mean literally saying yes. It’s about accepting the premise, not the proposal. The way it was taught to me, if you offer me a live hand grenade, I can accept the premise by saying “oh god he’s got a bomb!”, even though I’m saying no to the concrete offer to take your hand grenade.
“Let’s change everything” - depending on context - can be a no to the premise. It’s the same as the Pixar idea - improv is about making your scene partners look good by supporting their choices, and building on them in turn.
(e.g. "Oh BooBoo, how did you get on the shelf you silly cat?")
If an actor instead said "No, the cat wasn't on the shelf, the cat wasn't even in the room" the skit ends awkwardly.