Believing you can do something is often said to be a prerequisite to achieving it. Exactly how much it matters to the outcome I’m sure is up for huge debate, but small and large things alike in your day can be measurably impacted by your mental state, and visualization is an extremely effective way to alter your mental state in a given moment.
Weightlifters (even non-pro) will be able to identify with my own experience in reaching new PRs. Muscle activation in particular is some percentage physical and some double digit percentage mental. If you know you can lift that weight, it just doesn’t feel as heavy.
I’ve read that athletes often visualize their performance very viscerally to prepare their body to perform a routine. Reading the passage about a basketball dribbler thinking of himself being able to literally pass through other players on the court, to me is just a form of this positive visualiation.
To take it a step further, someone visualizing all that negative energy, turning it into a semi-controlled form of mass hysteria, absolutely has a significant physical effect on the people participating, and very likely also the people watching nearby.
The idea that this could work on a physically isolated subject who is unaware of the experiment would be the true revelation, but it is yet to be seen.
We do have “superpowers” in many ways, but unfortunately the laws of physics put somewhat of a damper on macro scale spooky action at a distance.