I’ve been running my own eMail server for almost a quarter century, and I have no clue what all the fuss is about.
Sure, providers are getting very picky about what domains that they will receive eMails from. But that’s why I have gMail, Yahoo, and Microsoft webmail accounts - so I can train their systems by exchanging emails once a quarter.
And yes, you do have to be running whitelists and blacklists and tarpits and have a good Fail2Ban in place. And good geoIP system if you want to cut out regions that you are unlikely to ever have legitimate mail originate from. But that’s just common sense security.





Now that ASP.net is multi-platform as DotNet, it should really be rotated through that list a second time, preferably around 2024.
Seriously, DotNet makes Java look like nothing has happened with it since 2008.
And even in terms of web work, Blazor WebAssembly is neck-and-neck with Rust, and is even beating it in speed for some specific configs.