Think of a really crappy text editor you've used. Now think of a really nice IDE, smooth, easy, makes things seem easy.

Maybe the AI being 'Nice' is just a personality hack, like being 'easier' on your human brain that is geared towards relationships.

Or maybe Its equivalent of rounded corners.

Like the Iphone, it didn't do anything 'new', it just did it with style.

And AI personalities is trying to dial into what makes a human respond.