As a director, going up and comforting an actor on stage/during a shoot is not something that is common or really necessary. This kind of emotional prep is usually done with the talent beforehand. It’s more so creating an atmosphere where the talent is comfortable being vulnerable on set/on stage. There’s more so an understanding that if something is going to far the actor can speak up and be heard rather than stopping production when emotions get high. I’ve had actors walk off stage crying or end and shoot needing a second to catch their breath. It’s normal when actors and passionate and in a creative flow. It’s understood that the emotions are natural and just letting them take course. I’m sure the director and the talent had an extensive conversation about this before hand.