My brother had a friend who tried to register fuck.com in the early days of the Internet, around 1994, and the registrar was confused and wanted to know why he wanted to register it. This was when the Internet was mostly universities and a .com cost $100 to register.
Was that friend Justin Hall of Wired?
There was a story about Jon Postel (pre-ICANN) and fuck.com, this might be it:
What was his response? Did they refuse to allow it?
1994 they were definitely still free[1]. I had so many good ones, but when they switched to the paid model[0] I was a broke college student and let them all go.
[0] IIRC, it was Unilever who caused it -- they mailed in something like 19,000 domain registration applications, one for each of their current trademarks.
[1] OK, I looked it up, September 1995 was when the charging started.