Great question and my gut is that it makes it that much easier for large, perhaps corporate interests to gain surveillance and control. I'm aware it's possible now, but it really feels like there's some safety in the friction of the possibility that my home devices just switch up IP addresses once in a while.

Like, wouldn't e.g. IPv6 theoretically make "ISP's charging per device in your home" easier, if only a little bit? I know they COULD just do MAC addresses, but still.