The hallway conversation thing befuddles me. Have you ever opened a chat window with someone at work to speak to them on the side? That's a hallway conversation

The hallway conversation thing befuddles me. Have you ever opened a chat window with someone at work to speak to them on the side? That's a hallway conversation. You can tell them any secret you want there. Have you ever seen two people interact in a group chat and learn something you didn't know before? That's the same as overhearing a hallway conversation. Grabbed a few friends in a group chat to chat about the weekend? Water cooler. The only difference is no one is going to tell you to be quiet and get back to work. No one is going to send an email about how there are too many people wasting time around the water cooler! I just don't see the advantage.