As someone who has had the stomach churning task of firing people, jokes like this don't seem worth it. How much good will can you earn by making employment at your company sound like a joke?
It's no different than the Monty Python and the Holy Grail credits running gag about those responsible being sacked.
It's a joke. It probably won't be funny to people who've just lost their jobs or to people who have recently had to fire others. And that's okay. There's a wide gulf between a joke that's distasteful or generally offensive and one that simply isn't well-received by 100% of its potential audience. This one is clearly the latter.