Email is basically the worst-common-denominator for communications and data transfer. It's going to keep existing forever because it's the one thing that basically everybody has and everything can support, but from the perspective of security, usability, and especially structured data transfer it's terrible.
I can't think of a reason I'd want a decentralized system to use email as the message bus. I do want the message bus to be backed by something standardized, but there's plenty of standard ways to transmit data that aren't SMTP. If some users want to interact with the system via email, supporting email as a notification / response mechanism is totally viable without using that as the backplane for the service itself.
I can't think of a reason I'd want a decentralized system to use email as the message bus. I do want the message bus to be backed by something standardized, but there's plenty of standard ways to transmit data that aren't SMTP. If some users want to interact with the system via email, supporting email as a notification / response mechanism is totally viable without using that as the backplane for the service itself.