I have 30,000 miles on my MP4, I always use the radio etc. I have experienced and been told the touch screens do wear out. The touch screen is a warranty item, all you have to do is show McLaren the areas you touch and get no response.
Bad news, if you do not have a warranty, there are two halves to the IRIS II and the top half is $8,000.00 plus labor.
I feel bad for those who rarely drive their McLarens, some of the things need time, miles to make sure they operate well. this is an auto which can drive all day long and is enjoyable, DRIVE your McLaren, do not let it sit. Enjoy it. I am thinking, once more is known about a McLaren, the higher miles ones will have a greater value because they will be perfect where as a lower mileage one will have all sorts of issues. a good example if my 1988 Porche Werks Turbo-Look. I have 216,000 miles on it. mine had never been rebuilt because I drive it regular. similar ones with under 50,000 miles need to have engines, transmissions, and suspensions rebuilt, what a waste... I also smoged my CA Porsche last week and was told it is the cleanest one he has ever seen, it passed smog easily.
Drive your McLarens, they love to be enjoyed daily...