I had to look that up
I had never heard of Walder Frey! I read the subhead and had to search for the name to find out who that was. I know who John McAfee is, though.
Despite billing himself as "the world's most famous hacker", Kevin Mitnick isn't the infosec personality your grandma is most interested in learning more about. That honour falls to Robert Herjavec, who is the most searched-for person on Google with an infosec connection, according to a list compiled by threat intel firm …
I'm familiar with Walder Frey and Game of Thrones, however describing the show as "some American sitcom about a metal chair." threw me for a moment. The show was filmed in Europe, had a mostly English cast and was shown internationally. Supposedly even based on historical British/Scottish events, as filtered through Martin's mind.
I've never have recognised Got from that rather (trying to hard to be a) Gen-X'er description.
I've not watched TV since 2012, i just assumed it was in reference to some sitcom about disability that managed to garner enough interest to reach a certain level of awareness, but not much beyond the non-TV watching public (say, somewhere between the second Roseanne and Big Bang Theory, but not as high as Friends - probably around Will and Grace levels*).
* There's no A.A. for TV - but I used to be a bit of an addict.