Before HTTPS was all but required for everything, an intranet site would get blocked in one particular office at 11pm every night. We tracked it down to a night-shift employee signing in, whose last name contained "shit". After pleading fruitlessly against that office's IT policies we solved the problem permanently by eating the overhead and turning on HTTPS.
I once debugged an email delivery issue which turned out to be a similar filter which included email headers while scanning, ending up blocking any email that passed through an SMTP server called foo.sussex.bar.hp.com (or maybe it was Essex, my memory is hazy).
The later (TV-Show) is actually based on the former (twitter feed) but couldn't retain the name in the US. It would probably have been perfectly fine as is in the UK.
I never understand that kind of (often self) censorship where the meaning is intentionally left clear. It could be malicious compliance with keyword-based filters but people do it voluntarily even in places where no such filters exist.
I make a point to mention that my cat’s full name is Robert. I enjoy the reactions: person either looks at me like I’m a moron for thinking this is something worth spending the energy to say out loud, or they really enjoy it. I digress.
It likely originated in rhyming slang where words that rhyme are used as replacement[0]. It isn't the only example in nick names. Bill is a nickname for William and Bob is a nickname for Robert.
The nickname for John is Jack, actually. Jack and Dick both belong to a class of nicknames that all end in "ck" or "k" sounds, but for which the original doesn't have a k sound.