We've done limited server play with friends. As far as I understand, anyone can download and run the server software (literally - it's a free download). To log into a server, you need the IP address (and need to understand how to port forward if going outside the home etc etc). P
I think my broader point is that I appreciate Microsoft saying they want Minecraft to be a profanity -free zone. There are plenty in the "online community" that seem to be quite happy being G-rated. My 9-yeae old has watched about 100 hours of YouTube from "Pixlriffs" and its been wonderful despite random zombie attacks or whatnot.