I’m running my own over 20 years now. For my own domains and catch all and temporary email address. For very long time temp email was not available commercialy. Now we have simple login, I think Firefox has something similar and few others. I would say it pretty self sufficient, no need to tinker when all is set up. I have always been exim user and I only know exim. The only pain I have now is that let’s encrypt certificate gets renewed every 3 months and exim is unable to read it, so I need to fix permissions. The bonus point and weired flex is the ability to read email via telnet to port 110 and sending email chatting to the server on port 25 lol