For the last year I've enjoyed the same level of email security as Hillary Clinton. I have a private server where my email is stored. It's a little white box that sits under my wet bar. What this has meant is that if anybody wanted to read my email, they'd have to get a warrant and come to my house or kick open my front door and get past me and all the tools at my disposal to resist such an action. I have no secrets in my emails, all I get is junk mail, receipts and notices to pay bills, and my main reason for having it is simply because I don't want google knowing what I've purchased or am thinking about purchasing. It's also fun to be secretive, I may not have a lot of secrets now, but what if I want to get some later? I like to leave the door of possibility open for such things.
Anyway, the provider, Helm, ran out of money. They were funded by Serena Williams' husband who is a venture capitalist and I guess most people are content with free email. After making it out to the other side I can't go back to free email. Helm simplified things while still giving me about 99% of the security, the tradeoff was of course that if they go away I have a huge learning task to keep the same level of email comfort and security I have now.
Helm says they're going to push out an update so that I can run a linux based server myself, but the complication will be if my ISP will allow me to open those ports. Many ISPs don't allow consumers to run email servers because they don't want spammers setting up shop.
Another issue will be setting up a static IP, which won't be free, but shouldn't be too expensive.
Worst case scenario I can use iCloud for email, they will host private domains, but I may be able to set up a VPS that runs a server... except that still leaves my data in someone else's hands, so I'm going to have to figure it out. I currently have my email set up as a catch-all, so any and all email sent to my domain gets routed to my inbox. That allows me to use a random and custom domain for ever new account I have to set up. Apple will give me a max of 5 email addresses and then force me to use their "Hide my email" service which I prefer not to use.
It's a shame more people don't care about owning their data, but I don't expect it to change anytime soon. In the meantime I will just have to learn how email servers work.