I wonder how many people died in Endgame from the reverse-snap. Think about it. If someone was driving at 70 mph when they got snapped away, 5 years later they'd find themselves floating 2 feet above the ground going 70 mph, and that's if there didn't happen to be another car in that same spot at the moment. And what if someone was in a plane?
And those aren't even the biggest issue here. What about the movement of the Earth?? Realistically, everyone who came back would soon die because they come back in space, unless they had planned to do their snap when the Earth was in the same place(which they didn't)
Of course, Professor Hulk could'v accounted for all this when he snapped.