Resolving assignments of cloned screens in the absence of physical-plugging-involving hotplug (that thus only comes from the monitor(s) also turning off when the laptop goes to sleep) by random instead of remembering physical ports/paths to them, across sometime as tame as a suspend-to-RAM, is frankly terrible UX.
Trying to use uniqueness features to be sticky across port swaps is good.... but I'd not be surprised if my grandparents would actually assume the way to swap them is by swapping the ports they are plugged into. Especially I'd expect them to be confused/surprised by swapping the plugs _not_ resulting in swapped content.