I understand what you mean, having had to deal with SPF nonsense for a job back in the day. The SPF nonsense is what prevents selfhosting email, as you effectively point out yourself. If there were somehow a way to use federation to tackle that, it seems like it could be kinda cool.

Decentralized email? I feel like I could get behind that

There are a significant number of people who refuse to support Brave due to its CEOs support for anti-lgbt legislation and donations: https://en.m.wikipedia.org/wiki/Brendan_Eich

Homeassistant?

Yeah it is? There’s a reason your dns confutation has a backup IP address.

Smoking the reefer!

And?