In eSport where the only physical movement is a couple mm of their hand that may be true. In the physical world where these things involve several inches or more of movement with large muscle groups...ehhh no.

Gunfighter hypotheticals aside you can watch it play out in the real world during any soccer game. The attacker who makes the defender react to them slips past while the defender who makes the attacker react wins. The attacker who makes the goalie react has an open net, but if the goalie can make the attacker react then they block the shot (or it misses).

No matter the physical sport, Soccer, Basketball, Rugby, Volleyball, if it has 1 v 1 elements then "juking" works and the reason why is because it makes the other player reactive.

You've got that backwards, Peakers Advantage is a well known element in competitive FPS.

It has nothing to do with the human, and everything to do with the computer, but eSports players absolutely know it's better to peak.

This lacks a lot of context as both strategies are useful in different circumstances. For a player (A) holding an angle from a far distance, this is true because the person coming around the corner (B) from a short distance to the corner is visible to to A before A is visible to B. This gives the reactor an advantage. This is usually afaik called angle advantage

For a person who is close to a corner peeking a person close to the corner, the opposite can be true due to the delay it takes for the movement to be relayed to the other player's computer. This means that the player peeking may in more extreme cases have a 100-200ms advantage over the reacting player. This is dubbed peeker's advantage.

The effects can vary with latency and distance,