"Which, if (as you should) you assign addresses randomly, improves your protection against network mapping and hence port scanning, even if you do accidentally forget to do ingress filtering."
This implies that the LAN owner has to do stuff. For a large enterprise this is fair enough - they can pay for people to do it* - but for small businesses and home users it's a no-no. Unless the whole thing comes configured with such sensible default options it's going to be addressed along the lines of "what we have works - don't need anything else".
* and, in theory, to be trained if they're not already equipped with the knowledge although enterprises tend to treat this as optional, default off.