Why are coaches allowed to speak to players during the hydration breaks?

(Disclaimer: I am not much of a football fan so I’m looking for educational responses, not s—t talking)

One of the complaints I’ve seen from soccer fans about the hydration breaks is that it gives the coaches an opportunity to talk to the players.

So why allow it? Why not just have the following rules:

1. the players may not leave the pitch and must gather near the 1/2 circle at the top of the box
2. the coaching staff may not go on the pitch
3. only the athletic training staff may go on the pitch, only to carry the beverages, and they may not speak to the players.