Kanban boards are fine tools for the right situation. They are indeed pretty much a ticketing system, and you've probably used one. Most short order kitchens use one.
It's not about the tool, it's a way of modelling a live process. In the kitchen example you might have a single written order that several people want to look at, and it's a waste of time to have someone read it out to you. Same way for assigning coding tasks, cleaning rosters etc.
They are mainly effective when you have an already efficient self aware workforce, and zero use if you have to do any explanation about them each time someone wants to use them.
They are simple enough for a four year old to use, hence the appeal to manglement types. They might not understand the words on the post-its stuck to the whiteboard, but they do sound like good things.