You're right, but I'd use the word 'trick' over the word joke. There is no trick that would pass my scrutiny to be okay at work, that's why I replied the way I did.

Jokes like one liners or what stand up comedians do are usually more acceptable in my eyes. I have yet to see a joke used for April fools. If you have an example please share and I might do it next year.

In the end, I really don't care, if the joke/trick lands and no one was upset then take the win. You know your environment and are making it a better place.