These aren't web technologies at all, but firewall issues. This doesn't have anything to do with websites being inefficient, but how some firewalls handle some ICMP edge cases. I feel like the complexity of IPv4/6 is high and stuff like this will continue to be found. If you want a world-wide networking protocol, you need to deal with complexity, and complexity comes with issues like this.

We should be geared up to fix stuff like this via quick patching. This stuff shouldn't be terribly surprising. I think the idea of "install and forget" for any internet enabled device is a dangerous line of thinking, especially for firewalls.