The way I understand their mechanism, it lets you log in on a separate device, but will complain if you don't connect that device to your "household" wi-fi within a few days, and will then force you to either stop using your Disney+ account on that new device, or to transfer your "household" to its current wi-fi network, disabling the devices on the old network, and giving you a limited amount of such transfers.

So it's ok for phones/tablets/laptops that get moved around, but blocks usage on PCs or TVs across networks.