To add some color from our end to this discussion:
It's great to x-post from Medium if you're used to publishing there and don't want to add too much burden to your workflow
It's great to x-post from your own site to establish a canonical source for your own work. For some this is definitely important and we want to support this.
dev.to has some native functionality that you'd only get here, largely expressed as "liquid tags" in the markdown. But we'll always be compatible with most RSS feeds.
As we keep growing, "best practices" in this regard might change, but we really care about backward compatibility, so expect us to be driven to not sweep the rug from under you.
To add some color from our end to this discussion:
Thanks for the tip on the rss driven auto x-posting. That could be useful.