SMTP, HTTP, FTP, Telnet, SSH, SFTP,Finger Are all relatively easy to self-host. and it used to be frequently done.
We have plenty of protocols to use already, and we have had them for a long time, that is not the problem.
In my country none of the main ISPs offer static IPs. They're only available to businesses.
Self-hosting with a dynamic IP seems difficult if not impossible. There are some dynamic DNS services but that kinda defeats the self-hosted part.
You just need something on your network that monitors your IP and updates your DNS when your home IP changes. "Dynamic DNS Update Client" yields results in Google that will be a good start to understanding.
> There are some dynamic DNS services but that kinda defeats the self-hosted part.
No, selfhosting at home doesn't mean you have to host a public DNS server. You will definitely need some external DNS pointing to your home network. There are multiple free providers.
If you try to do it from a VPS, they have usually blocked entire segments of the companies IPs. (Because someone, a lot of someones came before you)
There are good reasons to right spam. But the efforts of the biggie names are forcing people to use their services. (Its free after all right)
It what I now realise was a bad idea, I was writing code by web server code using C with CGI. I was supposed to use Perl, but I didn't want to spend time learning that as I already knew C.