I don't know if it can help you, but I finally figured out what was "wrong" with my document. I had the artboard I was working on locked. Once I unlocked it, I could use the move tool in the "tap to select" way again. And every time I have the artboard locked, I have to drag the arrow to select my objects.
Hello, could you find an answer to this issue ? I think I have the same problem : when I want to use the move tool, I have to drag the arrow over the object to select it instead of being able to tap on it. But this happens only on a particular document. When I’m working on any other document (new or not) the move tool works as expected (meaning I can tap to select an object). So I thought maybe this can come from a setting that I activated without knowing ?