If it has no function, it surely would be a nice button for your garage opener. Easy to add that under the panel - I did that on my old ST1300, which had a similar button on the handlebar cluster - PO used it for his communication setup
Opening the garage door has to be done without having to stop or use devices that you may or may not have handy. Therefore, it has to be a bike-mounted solution for me. I have now had my garage door opener mounted beneath a panel for years - connected to a small button. I love it - and it's very discreet.