Email newsletters used to be a newsletter that I believe used to be sent through email a few years ago. I am not sure if most people even check emails anymore.
Now, people post content on social media like Mastodon or send direct messages to people or groups through XMPP or Matrix.
@textovervideo @hejowhat Email newsletters are still a thing, and in fact are on the rise in recent years. Although certain demographics are less likely to use email, it's still a safe bet than you can reach practically anyone on the internet using an email address. The same can't be said of various social platforms, however big they are.
Fosstodon is an English speaking Mastodon instance that is open to anyone who is interested in technology; particularly free & open source software.