The datalist examples definitely work on my iPhone. They integrate into the autocomplete suggestions above the native iOS keyboard. There’s no way to browse all the suggestions, but I suppose that’s not an intended use case for datalist.
However, the disabled attr on group definitely does not work!
That’s funny, in my case it tries to autofill my contact information
It seems the autofill bar only populates with the first three items in the datalist and also does not clear when navigating to a regular text field like this one. Kind of an interesting way to have screwed it up.