They're talking about the hallway chats that happen after the meeting, when people move from the conference room back to their cubes. Gotta talk about something as you walk, and if that happens to be in the form of a misrepresentation of your work, you not only can't do anything about it, but you'll never know. In my experience, that's more a reflection on a poor org than the situation. Before the pandemic when I wanted to have a hallway debrief with my coworkers in the office, I pinged them as such and we talked via Skype (then, it was years ago) about the meeting. Sure they'd started without me, but caught me up. It was fine.