Sorry, I should have been clearer. Those switches work great with fans that are already hardwired for a switch in the wall but a lot of modern fans (in my experience, maybe because I was buying cheap!) don't bother with that and have their own wireless system of some variety to control fan speed, lights etc.

My solution to that was to buy a Zigbee controller to go inside the fan. I wish Lutron sold some kind of standalone fan controller you could shove in there but alas.