This is not true at all. Avoiding McCree's ult is almost as easy as avoiding D.Va's
I can see hers coming. I know from which direction. You don't know which direction you need to run with high noon. There are no physical identifiers which direction it will come from unlike all those other abilities. I've side strafed around a corner hiding behind a wall when I've heard it only to be still dead because of flanking or he's behind us. Every other ultimate I can see where death approaches from.
If there is and I've missed it. Let me know.