Hi,
Sorry for the issues you are having.
I tested on my iPhone with the latest iOS in Safari and was able to use the iCal Export Button and it worked for me.
It asked if I wanted access to my contacts and I accepted if you previously denied that request it might not work for you.
It looks like we already have in place the coding for Safari to accept this.
Please note it will not work in other mobile browsers like Chrome. It will only work in Safari.
Let me know if you have any follow up questions.
Thanks