Feels sloppy (is sloppy) but I think the idea is to prioritize OS unification for hardware reasons, and UX across product suite — devices can share data, apps, screens, everything.

I'm seeing a lot of comments here about macOS/iOS unification, but I think people are getting worked up about nothing.

What do macOS window styles have to do with iOS? iOS (mostly) doesn't have windows!

What does the MacBook Neo have to do with iOS, other than coincidentally using some of the same components? Maybe Apple decided to make a cheaper Mac because they thought people might want to buy a cheaper Mac.

They are trying to use a common design language across all their devices, sure. But you would hardly expect them to do the opposite! They might try to make a hybrid tablet/laptop or something at some point, sure, but none of their current moves point inevitably in that direction. Except maybe for software notarization, but that has nothing to do with window corners or cheaper laptops.