I wouldn't get too grandiose about saying the institutions are broken. It's just email, why not consider it like postal mail? Definitely not good, definitely needs to be fixed, but also definitely does not mean the legislature entirely is not secured or that institutions are all broken.
It is critical infrastructure. There are two parts: a.) mimic the thing our predecessors created: postal mail was so important that they had a person on a steed ride across barren land for days to deliver a message; b.) how do we adapte the modern equivalent. It's not so hideous for someone to make a copy of the payload on the horse, is it? It's not good to copy it. But it's much worse if the original is compromised: faked message or faked originator or destroyed.
It demonstrably doesn't fulfil that need; GP's point, I think, is that postal mail has (perhaps more obvious, especially outside HN) vulnerabilities that were coped with for millennia.
