Sure there are a few others. What I’m mainly getting at is that you can’t run an email server in your house the same way you can run a lemmy instance and expect those emails to get delivered. You are forced to use someone else’s email service as a backend or google will flag your emails as spam.

This used to be true. However in the internet of today, if your email doesn’t come from a Microsoft or a google it will get rejected if the recipient is a Microsoft or google email address. They have taken over.