[Question] Does anyone run their own email server?

All this new excitement with Lemmy and federation has got me thinking that maybe I should learn to run my own instance. What always comes up though is how email is the orginal federated technology.

I am looking at proxmox and see that is has a built in email server, so now I am wondering if it is time to role my own.

I stopped using gmail a long time ago, and right now I use ProtonMail, but I am super frustrated with the dumb limitation of only having a single account for the app. I get why they do it, and I am willing to pay, but it is pricey and I don't know if that is my best option. I guess it is worth it since ProtonVPN is included. It looks like they are expanding their suite.

Is it worth it? Can I make it secure? Is it stupid to run it off a local computer on my home network?